A LIFE LESS ORDINARY

A British aid-worker meets the leader of a violent guerrilla movement in war-torn Sudan - and falls madly in love. If Emma McCune's story were a movie, you wouldn't believe it

WHEN I think of Nasir, I remember the sun. Nothing in that place escaped it. Perched on the great savannah of north-east Africa, Nasir lies 100 miles east of the White Nile and 80 miles west of Ethiopia. Early in the century the British established a command post there over the local tribe of extremely tall and fearless cattle-keepers, the Nuer. But when I went there, Sudan's civil war had destroyed most of the old town. The United Nations was delivering food at a crude airstrip made from the rubble of evacuated buildings. The rebel Sudan People's Liberation Army (the SPLA) had located their provincial headquarters a few miles up the Sobat River from the ruins.

I remember how desolate it was, and I think of Emma. I met her there in 1990. I was working for an American newspaper; she worked for a Canadian relief agency. She had not yet scandalised the region's aid workers by marrying the local warlord and going to live with him and his gunmen in a mud compound on the banks of the Sobat. But even then there was something unsettling about her.

I had been in Nasir for a week, reporting on the war between the Islamic government in the north and the non-Islamic (pagan and Christian) rebels in the south. I had been interviewing teenage soldiers and starving children: since the war began in 1983 perhaps a million people had died, a quarter of them in the war-made famine of 1988. Still, there was an eerie beauty to this part of southern Sudan. The years of fighting had sealed the area off from modern life, turning the swampy land between Ethiopia and the Nile into a vast wilderness, interrupted only by occasional bombings and machine-gun fire.

At the end of the week I went to the airstrip and waited for a United Nations plane to fly me back to Kenya. The plane came down in the tight corkscrew that the pilots always performed in case someone shot at them from the ground. The engine died, the door opened, and out jumped Emma. She was six feet tall, as slender as a model, and she was wearing a red miniskirt. An SPLA officer was with her, and they were laughing together about something. It was hard to believe that she was flying in on an emergency relief mission. She looked as if she were stepping out of a private plane to go to a party.

In a way I was not surprised. I had heard about Emma: she was young, glamorous, energetic and idealistic, and had sent a ripple of excitement through the social circles of the aid business. In Nairobi - the headquarters of the humanitarian industry in East Africa - she had a reputation for wildness: adventures in the bush, nightlife in the city. She was an Englishwoman said to feel at home only with Africans.

Now, in Nasir, I understood the undercurrent of disapproval that followed in her wake. That gorgeous splash of a miniskirt seemed almost indecent in a place filled with sick, hungry people catching their breath between bouts of famine and vicious killing. To look happy seemed tactless - a flaunting of one's good fortune. It occurred to me that the unofficial uniform for most of us Westerners - blue jeans and T-shirts, modest shorts - was one way of desexing ourselves, at least in our own minds. It announced: "We're not here to have a good time." It was like a surgeon's scrubsuit, or maybe a modern version of sackcloth and ashes; an unspoken signal that we were wiser than the Sudanese, and in a kind of mourning for them and the things they did. Not that the Sudanese were fooled. The truth was that the average Western aid worker or journalist delighted in the buzz, the intensity of life in a war zone, the heightened sensations brought on by the presence of death and the determination to do good. We wanted to be here; we were paid good money to be here; and the Sudanese knew it.

Emma's miniskirt seemed a refreshing departure from the usual pieties. It suggested that she was more honest than the rest of us, that she wasn't afraid to admit that she was here because she wanted to be.

Emma and I exchanged pleasantries, nothing more, and I didn't see her again for a long time. But I began to think about her for another reason, which had nothing to do with clothes. In Nasir, I had spent days interviewing the SPLA's "education coordinator", a man named Lul. He had claimed to be a great friend of hers. He was the sort of man his fellow Nuer used to call a black Turuk - a black man who wore clothes and could read and write and had adopted some of the ways of the Ottoman Turks and other foreigners who'd invaded Nuerland a century and a half earlier. Like most Nuer, he was black as a panther, tall and thin with a narrow head and a loping walk. Lul was a former schoolmaster and an elder in the Presbyterian Church. He was also a bore and a bully. He would recite SPLA slogans with noisy fervour, insisting that southerners would never settle for anything less than a new, secular government for the whole of Sudan, though less than a year later he was to be equally enthusiastic when Riek Machar, the Nasir-based leader of the Nuer, split from the SPLA and formed a new movement that wanted the south to secede and become independent.

Emma was working with Lul to try to reopen Nasir's schools, which had been closed for six years because of the war. I wondered how she could stand it, listening to him raving on day after day about fighting for a hundred years to create a "New Sudan" in that blinding emptiness. But according to Lul, he and Emma got along famously. In fact, he was more interested in discussing Emma than the schools. "You know, Em-Maa" - he pronounced her name with a satisfied smack of his lips - "is just like one of us. She walks everywhere without getting tired. She is bringing us so many things we need, like papers and chalks and school books. You people should know, our commander likes Em-Maa very much. Very much!" Underneath all the praise there was something leering in the schoolmaster's voice.

When I learned, six months later, that Emma had actually married Riek Machar, the commander Lul had been talking about, the one who liked her "very much", I remembered that mingling of lust and envy and contempt in Lul's voice. Naturally I knew of "Dr Riek". A black Turuk, like Lul, with a PhD from Bradford University in England, he was the best-educated Nuer in the ranks of the SPLA. Westerners found him unusually sophisticated and amiable. But though I knew Emma only slightly, the news of her marriage provoked a jumble of emotions in me. At 27, she wasn't much younger than me. And the world of the khawadja - the Sudanese term for white people, the aid workers, journalists and diplomats working in Africa - is a small one, so we shared many friends and acquaintances. I had been writing about Sudan, off and on, for three years: it was the furthest and deepest part of my experience. Now here was Emma going further and deeper than I had even imagined, crossing over from the aid world into a violent guerrilla movement led by men like Lul, men responsible for some of the horrors she had been working to alleviate. What, I wondered, drove her to take such an extreme step? It occurred to me that her story might shed some light on the entire humanitarian experiment in Africa. Or at least on the experiences of people like me, who went there thinking they could help, and came back numb with disillusionment.

And this was before I learned that Lul was later tortured to death, probably by supporters of the man Emma had married.

WHERE DID Emma come from? In London I went to see her mother, Maggie McCune, a trim woman who looks like what she is - the crisp and competent secretary to the registrar at St Paul's Cathedral. She still calls herself an ex-colonial, though the imperial sun was setting by the time she was born in India in 1942. Her parents had been British tea planters in Assam; and she met and married Emma's father, Julian McCune, in India in 1962. Julian, the child of an Irish father and a mother from Yorkshire, was an engineer who had knocked around Britain's colonies for more than a decade before settling down with Maggie at a tea plantation. But by the time Emma and her sister Erica were born, it was plain that there was little room in the post-war world for men such as Julian. The Indian government had started nationalising the tea companies, replacing British executives with Indians. Julian considered going to South Africa, but Maggie wanted to spare her children the loneliness of her own colonial childhood at boarding schools in Britain. The McCunes moved to Yorkshire when Emma was three.

Emma's father took a job with a security firm, and bought a country house near Bedale, on the edge of the Yorkshire Dales, large enough for what would soon be a family of six - Jenny was born in 1967, and Johnny in 1970. But Julian was restless. He never got used to being back in England. He became involved with a woman; there were money troubles. When Emma was 11, he killed himself.

Maggie McCune, who had never been trained to earn her own living, suddenly had to provide for four children. She was forced to sell the house and move them all into a cramped little flat. Somehow she managed to find the money to keep Emma in private schools, first at a Yorkshire convent and then at Godalming College in Kent. Emma was never cerebral, but she was smart, and had a gift for getting people to do what she wanted. In 1982 she was offered a place to study art and art history at Oxford Polytechnic.

I asked Mrs McCune how she thought her husband's suicide had affected Emma. She said only that she thought it made Emma "less materialistic". Some of Emma's friends think it might have helped create a split in Emma's psyche - between the sensuality and freedom she linked with her father and abroad, and the frugality she associated with her mother and England. In any case, by the time she left home for Oxford, Africa already beckoned.

She was 17 and in her first year at the polytechnic when she met Sally Dudmesh. Dudmesh holds a British passport, but was raised in Africa and considers herself a white African. She designs jewellery in Kenya, though when I talked to her she was visiting friends in Sussex. There was, she said, an instant attraction between the two. The first time they met, Emma was wearing a long purple velvet kaftan. She was pale and darkhaired, with a seductive whisper of a voice. "I felt like I was meeting my own sister. She always dressed exotically. She had a wicked sense of humour. At that time, she was really arty. She had a really fun, bad- girl side." Dudmesh felt sure that Emma was drawn to her because of her connection with Africa.

Dudmesh lived with Willy Knocker, a white Kenyan. Emma joined a circle of would-be Africanists in Oxford who liked to wear African clothes, listen to African music and talk about African politics. These students saw in Africa an escape from the restraint of middle-class English life. "It was just a sort of wildness, a spirit of adventure," said Dudmesh.

Emma's Africa-loving friends envisioned Western lives against an exciting big-sky backdrop; but Emma sought a more intimate connection. She was always attracted to African men (later she would joke that white men made her think of earthworms) and especially to African men with power: politicians and generals. On the surface her views on Africa were conventional; mostly liberal platitudes. But underneath she seems to have been instinctively attracted to the high drama of it all, the almost Shakespearian sense that, behind the sham parties and borrowed ideologies, character is all. She spoke of economic development and Western imperialism, but dreamed of heroes, kings and queens.

In her last year at Oxford she took up with a former Sudanese government official, an elegant Muslim intellectual and a well-known critic of Western aid efforts who worked at the Refugee Studies Programme in Queen Elizabeth House. She had volunteered at the centre herself - this was the time of Band Aid and Live Aid, and the programme had a hip aura. When she graduated in 1986 she went, on the centre's behalf, to the refugee camps for Ethiopians in the eastern Sudanese desert.

The trip was not a success - apparently Emma got nowhere with a plan to start a refugee newspaper - but on the plane back to England she met another former Sudanese official. He too was twenty-odd years older than her, but they became lovers. He took her to stay with friends of his near Oxford: a redoubtable British mother and daughter with old ties to Sudan. Dorothy Crowfoot Hodgkin, a scientist who won the Nobel Prize for Chemistry in 1964, had grown up in Sudan, where her parents were teachers. Her daughter, Liz Hodgkin, had spent several years teaching at the University of Khartoum; she now works at Amnesty International in London.

The Hodgkins were disconcerted when their married Sudanese friend turned up with a young British girlfriend. But they quickly agreed that Emma was a "wonderfully interesting person" and invited her to stay. After a few months, Emma decided to enrol at London's School of Oriental and African Studies for a master's degree in African studies. She and Liz Hodgkin moved to London together. Emma found a part-time job at the Sudanese cultural centre in Knightsbridge. For a while she lived with an Ethiopian man, but after they broke up, she seems to have decided that her future lay in Sudan. Liz Hodgkin said that Emma told her she didn't understand Ethiopians the way she did Sudanese. "I just don't know what they're thinking," she said.

Emma's supervisor at the School of Oriental and African Studies remembers her well. "She was one of the better students we've had," said Michael Twaddle. "A very original person." In 1988, evidence began to come out of Sudan that the government's tactics in the civil war had created a great famine in the south. Emma and Liz Hodgkin joined several London groups trying to promote peace. With Twaddle's help, Emma and some of the other members started a newsletter to collect information about Sudanese human-rights abuses. The first issue of Sudan Update, as it was called, came out in June 1989, the same month that Islamic fundamentalists overthrew Sudan's weak but elected government in Khartoum. A few months later, Emma took a job in southern Sudan. She was 25.

Twaddle never asked Emma why she wanted to go to Africa. "We take it as a given that we're all hooked," he said. Nor was he surprised when she married a guerrilla. "People who get involved in Africa," he said, "often do get involved in terrible things."

IN A 1993 television documentary, The Warlord's Wife, Emma told her interviewer: "Sudan has a magic that takes hold of you for better or worse." She added: "It's not a very beautiful country; it's the people who are so charming." Foreigners entranced by the Sudanese often speak of their charm. But for the British television audience watching shots of Emma (languid in a pink leotard and long flowered skirt) juxtaposed with familiar African scenes - soldiers training, dying babies - the question must have been: If they're so charming, why do they keep killing each other?

In 1989, the standard journalistic answer went something like this. In the north, a Muslim government was determined to turn Sudan into an Islamic state. The non-Muslim south was fighting back. An American-educated former military officer named John Garang had formed the Sudan People's Liberation Army to lead the rebellion. Garang wanted to abolish Islamic law and create a national government that would give power to dispossessed people all over the country, not just in the south. The war started in 1983, though in a sense it was the resumption of a southern insurrection that had broken out soon after Sudan gained its independence from Britain in 1956. That round of the civil war had ended with a rickety peace in 1972, which gave the south regional autonomy. But the north, home to the Arab tribes that had devastated the south with slave-raids in the 19th century, proved unable to overcome its contempt for its darker-skinned, culturally African countrymen. The bigger southern tribes like the Dinka and Nuer, Nilotic cattle-herding warriors, rose up again rather than accept second-class status.

Like all such answers, this was true - but it wasn't the whole truth. Islam and Christianity were indeed part of the equation, but so were tribal and personal antagonisms less visible to the foreign eye. And money - especially money. As a political community, Sudan was to a large extent an illusion, a vast confidence trick promoted by the country's literate elite as a means of getting foreign aid and investment. Inevitably, when the jobs and money started to dry up, people fell back into more traditional tribal groupings. The north had what was left of urban life and a government. The south had oil, timber, gold and water. The war was messy: sometimes it seemed like an interminable series of bloody cattle-raids, with one side or the other constantly burning enemy villages so that they could herd away women, children and livestock. Most people were so poor and dulled by violence that plenty of them were willing to kill in exchange for some cows, a pair of trousers or a meal of sour sorghum bread.

There were also outsiders, kindling the flames for shadowy reasons of their own. Ethiopia's dictator, Colonel Mengistu Haile Mariam, wanted to retaliate against the Sudanese government for harbouring his enemies: the government of Sudan was sheltering the secessionist rebels who were eventually to overrun Ethiopia's government in those refugee camps Emma visited on her first trip to Africa. So when John Garang mutinied against Khartoum, Mengistu invited him to Ethiopia.

One long-time British investor in the region was Tiny Rowland, president of Lonrho Corporation and then owner of the Observer, and a career meddler in African politics. Whenever Garang or one of his associates went to London, they stayed at Rowland's Metropole Hotel. Rowland once commented to a business colleague that he "had the future of Sudan in the palm of his hand". When I spoke to him (on the telephone to his country house in Buckinghamshire) he stood by that statement. "I've been involved with Sudan for over 40 years," he said. "I was a founding member of the SPLM [the Sudan People's Liberation Movement: the political face of the SPLA]. All their uniforms were supplied by me - boots, everything. I still have a warehouse full ... I've put about pounds 20m to pounds 30m of my own money into the SPLM."

Riek Machar joined Garang's movement in 1984, five years before Emma arrived in Sudan. To most Western aid workers and journalists, he was just an unusually genial SPLA officer. But as the grandchild of a famous Nuer warrior-prophet, and the possessor of a rare advanced education, he was rather more important than we realised. John Garang was a member of the south's largest tribe, the Dinka. Both cattle-herding peoples, the Dinka and the Nuer were old rivals - with some three million people, Nuerland spreads across an area the size of England. When Riek joined Garang, it was part of a conscious attempt to unite the two tribes in common cause against the government. Riek told me that back in 1983, when he was finishing his doctorate in England, a private "contact" arranged for him and a group of southern Sudanese students to visit Libya's Colonel Gaddafi in Tripoli and John Garang in Addis Ababa. It was on this trip that Riek decided to join the SPLA. Riek didn't tell me the name of his "contact", and Rowland couldn't recall that particular student trip. But Rowland was confident that he must have been the man who paid for it. "Oh yes," he said. "Gaddafi gave me power of attorney for four years. He's a very dear, close friend of mine."

EMMA'S JOB, in this combustible situation, was to organise a schooling programme for southern Sudanese children. Schools had been closed throughout most of the south for up to six years by then. The north had an old, if not especially deep, tradition of literacy, owing to its contact with Islam and, before that, with Christianity. But reading and writing were unknown in the south before the foreign invasions of the 19th century. At the time of Sudan's independence, only a few thousand of the several million people in the south's two largest tribes, the Dinka and the Nuer, knew how to read and write. Their helplessness before the mysterious powers of "paper" contributed to their feelings of cultural inferiority. One of their main grievances against the north during the years of peace was Khartoum's failure to open more schools for southern children. In truth, the years of war had done more than the most diabolical northern government could have to thwart southern education. A century and a half after the first foreigner invaded and "the world was spoiled", as southerners say, still only about one in 20 southerners could read.

Emma's programme was the pet project of Peter Dalglish, the founder of the Canadian aid agency Street Kids International. Dalglish is a bouncy Canadian who gave up his legal career after visiting a famine camp in Ethiopia in 1984. He left his law firm for Sudan, where he eventually became involved in Operation Lifeline Sudan, a Unicef programme set up to ease the famine of 1988 by shipping food from Kenya to the rebel-held areas of the south. Dalglish had a British friend at Unicef called Alastair Scott-Villiers (who happened to know Emma from Oxford). In 1988, Scott- Villiers visited parts of the south that had been closed to foreigners for years. After five years of war, only a few hundred bullet-pocked and mostly roofless buildings were left standing in an area three times the size of Great Britain. Wasted refugees wandered through the grassy swamps towards the camps in Ethiopia. So many skeletons lay alongside the path to Ethiopia that the Nuer called it "The Trail of Bones".

In some places, Scott-Villiers encountered bands of skinny young boys marching under SPLA guard to Ethiopia. The rebels claimed that the boys were orphans, but the aid workers knew that the SPLA was encouraging Dinka and Nuer families to send their boys to the big refugee camps across the border - telling the boys' parents that their children might get an education at one of the UN-funded camp schools. In fact, most of the boys seemed to end up fighting alongside the rebels long before their education was completed or, in some cases, begun. The SPLA argued that reviving the south's schools was an important first step in the rebuilding of a shattered society. The Westerners saw the schools as a chance to keep southern boys from being forced to join the army. Scott-Villiers's wife, Patta, another aid expert, put together a proposal for Dalglish's outfit to fund a project. Patta knew Emma already, and suggested her for the job.

Emma accepted eagerly. Dalglish met her some months later, on one of his periodic visits to Nairobi. She drove up to the Fairview Hotel in the battered Land Rover she'd named "Brutus" (an early sign of her interest in rebel leaders). Dalglish, only a few years older than Emma, was smitten. "Who wouldn't be?" he said. "She was extremely dashing ... She was very compassionate. She clearly had a real interest in children, in helping kids."

Dalglish was impressed by Emma's flair. With help from the SPLA, she had somehow turned a small budget of around $10,000 into a network of bush schools. In just over a year her schools had about 25,000 pupils, most of them boys and girls who had never before attended classes. Emma found that there were more than enough literate southern Sudanese willing to teach in return for soap and salt, which were more valuable than money in the south's barter trade. She convinced Unicef to lend her two vehicles as well as other supplies. One of the biggest obstacles to her programme was the lack of books printed in the southern languages. Someone had discovered that the missionaries who had worked in Sudan a generation earlier still had the original printing plates for their children's readers in southern languages. The books were reprinted, and Emma gave them to her teachers.

It took Emma no time at all to figure out the political implications of her new role. She was giving southern rebels the UN supplies and teachers' salaries they needed to open schools - and, naturally, Khartoum opposed this, out of fear that it would bolster the rebels' authority. But Emma took tremendous pleasure in her power to bestow what the southerners saw as the ticket to a better life. "It was a wild place with a lot of opportunity for her," said Sally Dudmesh. "She had this incredibly powerful job. She was like the Minister of Education!"

Emma discovered something else about herself at this time: she was good at war. Once, she was caught, along with some other Westerners, in a government bombing raid on a collection of mud huts at Bor. Crouched in a shelter dug by the SPLA, the aid workers listened to the whistling of the bombs. When they crawled out, they saw bodies everywhere. People were screaming. Some children were alive, but shrapnel had cut off their legs. The SPLA medical team had run away. One of the aid workers, a Vietnam veteran, climbed into the UN vehicle and drove around in circles, maddened with rage. Emma remained calm: she seemed almost exhilarated by the situation. She radioed the UN to divert a plane to pick up the wounded, and organised the Sudanese to dig holes for their dead.

AT THE end of May, in 1991, radio operators at the UN's Operation Lifeline Sudan office in Nairobi began receiving urgent messages from Emma in Nasir. As the representative for Street Kids International, she was allowed to use the UN radio in emergencies. She warned that hundreds of thousands of hungry Sudanese refugees were fleeing their camps inside Ethiopia and walking back into southern Sudan. She begged the UN to begin airlifting relief supplies to Nasir. She even requested a UN peacekeeping force to provide a safe haven for the refugees.

It was true that Ethiopia was in chaos. Just over a week earlier, on 21 May, Mengistu had fled the country as rebel forces advanced on Addis Ababa. The Operation Lifeline Sudan officials in Nairobi had no doubt that large numbers of people were on the move, but every single delivery of grain inside Sudan was subject to delicate negotiations. They knew that to Khartoum the idea of a peacekeeping force would sound like a declaration of war. They were furious with Emma for using their open radio to broadcast what sounded like flagrant rebel propaganda.

Alastair and Patta Scott-Villiers took a boat from Nasir to Jekau, a village on the border between Sudan and Ethiopia, to find out what was happening. On 29 May, they watched 15,000 people cross into Sudan. These people came from Itang Camp, which until three days earlier had been the largest refugee camp in Ethiopia, and one of the largest in the world. Without Mengistu's protection, the SPLA could not maintain its bases there. So on 26 May, the rebels marched all 150,000 of the inhabitants out of the camp. Over the next few weeks, about 130,000 of them arrived in Nasir. As the refugees walked the 100-mile route along the Sobat River from Jekau to Nasir, they were bombed by the Sudanese government and attacked by bandits.

There to meet them were the Scott-Villiers, from Unicef, and Douglas Johnson, an Oxford-based historian of southern Sudan on temporary assignment to the World Food Programme. They were joined by dozens of other aid workers, who set up beds and mosquito nets for themselves in the abandoned houses of the missionaries along the Sobat. But the relief officials had little food or medicine to give the refugees. Khartoum refused to permit the UN to expand the operation beyond daily flights of a single plane, accusing unnamed Western aid workers of violating the neutrality of Operation Lifeline. To their chagrin, UN officials learned that Khartoum was not wrong. When they arrived in Nasir they found Emma living with Riek in his thatched military compound at a place called Ketbek, a few miles up the Sobat.

Emma and Riek had met briefly in 1989, in Nairobi. They saw each other again when he passed through Kenya four months later. Then, in February 1991, Riek sent her a written invitation to visit him in Nasir. Planes were not flying there at that time, so Emma set off in a car with Willy Knocker. They drove 1,500 miles through the bush, along mined dirt tracks. Riek said later that when they finally arrived it was the first car to have reached Nasir in eight years. Two days later, he asked Emma to marry him.

And now, with thousands of withered refugees converging on the place, she made her decision. On 17 June, Emma and Riek announced that they were getting married that afternoon.

Patta Scott-Villiers, who had been organising workers to distribute food, was mustered into service as a bridesmaid. She ran around among Nasir's weed-covered ruins picking flowers for Emma's bouquet. The wedding was held in a little Presbyterian church built by American missionaries and badly damaged in the war. The church's Nuer pastor performed the ceremony wearing a pink bathrobe. Riek wore his fatigues. Emma was dressed in an Ethiopian white shawl, and was given a silver ring that Alastair Scott-Villiers had bought for Patta in India. Riek's fellow SPLA commander, Lam Akol, was the best man. Patta Scott-Villiers remembers that a huge red sun was setting over the grasslands as Emma and Riek walked through the mud to the church. The pastor recalls that Riek didn't seem to be paying any cows for Emma, as was the Nuer custom. Otherwise "it was just a regular marriage ceremony," he said. "Everybody was very happy."

The wedding struck Emma's colleagues as the kind of surreal sideshow that often accompanies awful disasters. When you see starving Rwandans or Somalis or Cambodians staring with such solemn dignity out of your television screen, you get the idea that such camps must be all emaciated children lining up for food handed out by sternly heroic aid workers. But in reality it is more like a Hieronymus Bosch painting - a hallucinatory sea of huts and figures and odd little nightmare scenes punctuated by the rare saintly cameo. I remember how shocked I was in a famine camp in 1988 when I heard that Sudanese soldiers were screwing the refugees. But it's a funny thing about those camps - the less food, the more fucking there is.

Power is naked in such places. It comes down to who has food and who doesn't. The aid workers try to cover it up, try to make the men with guns deny themselves in favour of the children and the women. The camp's rulers play along for a while, but then the mask falls away. The strong always eat first. Then the question for the aid workers is: are we doing more harm by feeding the men with guns than we would by letting everybody starve? In Nasir, the question arose more quickly than usual because there was less food to go around. And very soon some of the aid workers began to wonder where Emma stood in this dilemma - on the side of the refugees or on the side of Riek.

Riek's best man had his own fears about the marriage. With his small, pointed beard, Lam Akol looks like an ebony Mephistopheles. I had lunch with him in 1997 at a cafe in Nairobi. Spread out in front of us were papers detailing the subtle positions of the splinter group that Lam formed after he and Riek broke up a few years ago. Lam called it SPLA-United, but at that time it had united nobody much outside Lam's own Shilluk tribe. Clever, foxy Lam carries a briefcase full of such documents wherever he goes. Although Emma and the aid workers weren't aware of it, at the time of the wedding Lam and Riek - two of Garang's senior commanders - were in the process of launching a coup against their leader. For the previous year and more, Riek and Lam on one side and Garang on the other had been manoeuvring for position. It had started in 1990, when Riek visited Addis Ababa. Lam - who like Riek holds a PhD from a British university - was then acting as the SPLA's "Foreign Minister". He, Riek and two other SPLA commanders decided to talk to Garang about sharing more power with lower- ranking officers such as themselves.

Garang was not pleased. In fact, Lam and Riek agree that he might have had them both shot if it weren't for the fact that his patron and protector, Ethiopia's Colonel Mengistu, was growing weaker by the day. Garang could no longer rely on the Ethiopian security forces to do his bidding, so to build up support within the SPLA for Riek and Lam's arrest he started a whispering campaign against them. Meanwhile, Lam and Riek were canvassing other commanders to see if they would support a full-blown coup. By June, the situation was very tense. According to Lam, he and another of the plotters, Gordon Kong Chuol, were scheming in their mud hut when Riek walked in and surprised them with his news. Lam was amazed that Riek could be so irresponsible, at such a perilous moment. "I knew Garang would say she was an agent or whatever," Lam said. "At that moment I knew we had difficulty."

It was too late to turn back. In Nasir, the plotters heard that Garang planned to arrest Lam. They asked one of the aid workers flying to Nairobi to take an envelope to the BBC correspondent. It contained their "Nasir Declaration", a 13-point appeal for a new SPLA based on human rights and democracy. It called for an end to the stealing of relief food and to the conscription of child soldiers. It referred to "self-determination for southern Sudan".

Lam said he deliberately left that last term vague. But when the BBC correspondent flew up to Nasir a few days later for an interview, Riek started blabbing into the man's tape recorder about how the SPLA shouldn't bother trying to free the whole country, just the south. "There was no way of stopping it," said Lam, disgusted. Poor Lam: so clever, so devious, yet forever hobbled by being a member of a smallish tribe. He was obliged to let Riek take the lead for the same reason Garang was obliged to promote Riek. If Riek wasn't in charge, the Nuer wouldn't follow, and without the Nuer the rebellion would go nowhere. The mutiny, however, was in trouble from the start. Through bad luck or bad timing or bad judgement, Riek and Lam failed to secure the overt support of any senior Dinka commanders. By the time Emma returned to Nasir a few weeks later, the coup had already galloped off in directions they say they never anticipated.

RIEK HAD agreed when Scott-Villiers insisted that the Unicef food was strictly for refugees, not for soldiers. But once a few khawadjas had stayed long enough to start recognising faces, they spotted Riek's cook and driver lining up for rations. The aid workers frequently caught Riek's soldiers stealing, but when they complained, Riek threatened to expel them. Emma was a silent presence at these confrontations. To her former co-workers, it seemed that she had gone over to the other side. "She was no longer a colleague," said Wendy James, Douglas Johnson's wife, herself an Oxford University social anthropologist. "She represented the power."

For his part, Johnson was concerned about the SPLA's treatment of about 2,000 malnourished boys. These boys were among those who had gone to Itang camp in Ethiopia in search of an education back in 1988. Now Riek had settled them in a camp of their own, across the river from his headquarters at Ketbek. No journalist could visit Riek without seeing them - they were a pitiful sight. Photographers turned them into poster children for the relief effort. In UN language, the boys were "unaccompanied minors". In fact, they were accompanied at all times by about 300 well-fed soldiers, who claimed to be their teachers and insisted on handling the distribution of food to them. Nevertheless the boys kept dying.

The aid workers also noticed that the boys' rations of Unimix high-protein meal were disappearing. Some of them went to see Riek and Emma about it. While they sat chatting, Riek's servant served them some fried bread balls (called mendazis) on a bright orange plastic plate - just like the plates in the UN feeding kits supplied to the boys. The mendazis were uncommonly tasty, said one of the aid workers. "Oh, it's Unimix," Riek explained.

Johnson was appalled, by Emma as well as Riek. "She made a great crusade for children, but when things began to go wrong, she took no position," he said. Some of the other aid workers in Nasir did not judge Emma that harshly. It was so hard to pin down facts in Sudan, they said. To many people, Emma's transgressions, such as they were, seemed only a tiny piece in a much larger and more outrageous puzzle. When she left Nasir to visit Nairobi, they wished her well.

EMMA'S MOTHER was working in a London bank when Emma telephoned from Nairobi. Emma usually came to England for a few weeks each summer and her mother was expecting her. "I have good news and bad news," Emma said, sounding very far away on the international line. "The bad news is I won't be coming home for a bit longer. The good news is, I'm married!"

It was the first that Maggie McCune had heard about it. She offered her congratulations.

Sally Dudmesh knew all about the romance with Riek: Emma always stayed with her when she came to Nairobi. When she came home that night and went up to Emma's room, she guessed what had happened. "Oh my God," she said. "You've married him, haven't you? Why couldn't you wait?"

"I just couldn't," Emma said - and told Dudmesh all about the wedding.

When Emma returned to England in August, everyone could see that she was in love. She made a dramatic entrance to a friend's wedding in a designer dress, by Ghost, that must have cost several hundred pounds. "Who is that stunning woman in black?" the guests were asking. She liked to answer that she was the wife of an African guerrilla chief.

Emma knew that she was not Riek's only wife. Ten years earlier, in 1981, he had married Angelina, the daughter of a Nuer politician and schoolteacher. After their wedding, she went with Riek to Bradford University, where she had two children in three years. In 1984, when she was 21, Riek left her and the children in England, returning to Sudan to join John Garang.

Emma actually tried to call on Angelina that summer, having been told that this was the proper thing for a junior Nuer wife to do. Angelina refused to see her. Later, Emma was often asked how an avowed feminist could marry a man who already had a wife. She would speak about the importance of respecting African traditions. Sometimes she praised polygamy as more honest than the serial monogamy of the West. "You never have to worry that your husband is having an extramarital affair," she said in The Warlord's Wife. These remarks embittered Angelina, who really had to live by the traditions Emma claimed to admire. "Who would want to share a husband?" she asked me when I visited her in the north-London suburb of Kingsbury.

Of Riek's marriage to Emma, she said: "It made me feel as if I had wasted all of my years." She had wanted to divorce him - she had grounds under Nuer law because he had not asked her permission to take a second wife. She said she presented Riek with her ultimatum two years later when he visited London for the first time after his second marriage. But Riek didn't pay much attention. On the contrary: when he left, Angelina was pregnant again.

Did Emma feel betrayed when Riek slept with Angelina? Later, Riek told me that the only betrayal she ever complained to him about was something else that occurred on her trip to England in 1991. On 28 August Emma was in London when she learned through the BBC that her new husband and Lam had proclaimed their independence from John Garang. The BBC reported that Riek and Lam were calling for a new SPLA that would concentrate on creating an independent southern Sudan rather than overthrowing the Khartoum government. On one level, Emma was thrilled. She loved the rhetoric that condemned the SPLA's human-rights abuses and demanded greater democracy within the movement. But she was furious that Riek had kept such an important secret from her. She immediately flew back to Africa to confront Riek. "You can't take me for granted like that," she told him.

That, Riek said, was the last thing he ever tried to hide from her.

AT FIRST Emma seemed to think she could carry on as an aid worker in Nasir as if nothing had changed. She sent her boss, Dalglish, a long field report. "It said, 'I did this and distributed this much, and - PS - three weeks ago I married Riek Machar in a short ceremony in his community'," Dalglish recalled. Such breezy confidence was typical of Emma, and Dalglish was so enthralled that his first instinct was to go along with the marriage. But it was impossible. "My board said No. They said southern Sudan is already highly politicised. We cannot have the representative of our agency married to the commander of the area." The board wrote to Emma to say that because Street Kids International had to preserve its neutrality, it couldn't renew her contract.

Emma's friends in the aid business had warned her that this would happen. But Emma was strangely blind to the obvious conflict between her humanitarian work and her husband's war. Or did she just not care? She certainly regretted the loss of her $12,000 a year salary. She incurred almost no expenses in Sudan, and had saved enough to keep going for a while. But she liked to live well when she was in Nairobi and London, and would come to be irked by her lack of money.

But she was madly in love. Each dangerous move Riek took against Garang heightened her excitement. Even the aid workers were caught up in it. Everyone agreed that Garang's SPLA-Mainstream, as people now started calling it, was a secretive, dictatorial organisation. Some said the SPLA's leadership was a mafia bent on plundering the south for gold and timber and stealing aid money. Until now, southerners had had no alternative but to side with Garang against the Islamic fundamentalists. Emma's husband was offering them liberation from both. Emma had persuaded the UN to donate a typewriter and mimeograph machine to her education programme; now she used them to produce proclamations and manifestos in the hut she shared with Riek. She said once that it was "an incredible high" to get up from lovemaking to draft constitutions for an independent southern Sudan. She was 27.

Unfortunately, her new husband was no Thomas Jefferson. In September 1991, Riek's breakaway force began attacking the SPLA-Mainstream in Dinka villages near Garang's home town, Bor. Lam and Riek seem to have hoped to persuade wavering commanders to join their side by demonstrating their strength in Garang's backyard. Bor was bigger than Nasir, with a good airstrip which allowed the UN to deliver a lot of food, and the nearby villages were rich in long-horned cattle. Riek had started calling himself "Riek Machar Teny-Dhurgon" - after his grandfather, the celebrated Nuer warrior-prophet. As it happened, a new prophet had arisen in Nuerland, named Wut Nyang. Wut Nyang had been talking about how Riek was left-handed and how, around the turn of the century, the most famous of all the Nuer prophets, Ngundeng, had foretold that a left-handed man would be the salvation of the Nuer. Others claimed that Ngundeng said there would be peace once civil war came to Bor.

Amid such portents, unmarked planes started dropping mysterious bundles to the Nasir forces. Then, in late September 1991 - for the first time in eight years - Khartoum allowed a barge filled with grain to sail up the river to Nasir from the government-held town of Malakal. Garang was quick to accuse Riek of collaborating with the government against him. At the time, Riek and Lam denied it. But Lam later told me that they had indeed held their first meeting with the government negotiators that October. He added that the meeting was facilitated by the SPLA's old friend Tiny Rowland. "Yes," said Rowland, when I asked him about this. "I thought it was time they came to an agreement with the government. But Garang is an extraordinarily difficult chap. It wasn't just Riek Machar who broke away. There were a lot of us."

One of Riek's own men was scared by the growing anti-Dinka feeling in Nasir. Captain Michael Manyon Anyang was a Dinka himself, a former circuit judge in his early thirties and the SPLA's "relief coordinator" in Nasir. Michael spent his spare time studying Dinka and Nuer traditional law. Whenever the aid workers went to Nairobi, he asked them to pick up law books for him. He had been an outspoken critic of the split. He started visiting the UN camp in the evenings, telling the aid workers he was afraid. Then one day in November, he disappeared. Riek's security chief told the aid workers that he had been caught trying to set a landmine in the UN camp. Amnesty International later reported that Michael had been executed.

When I asked Riek what was hardest for Emma to accept about their life together, he mentioned two "murder cases". "A judge, Michael Manyon - that person was murdered," he said. "We heard the shots. And there was another person, a medical assistant ... Up to today, we did not trace who killed them."

Later, when I spoke to Lam, he found Riek's account hilarious. Michael was executed at night, he claimed, on Riek's orders. So far as Emma's friends were concerned, the main thing was that she took Riek's side regardless of what he did.

Scott-Villiers was in Nairobi in November 1991 when word came that Dinka were being massacred at Bor. The UN had evacuated its people weeks earlier. Riek's group started issuing press releases along the lines of "Bor Captured, Great Victory". Before long, Operation Lifeline couldn't hold a relief meeting without rebel factions screaming recriminations at each other over Bor. It was decided that Scott-Villiers, some private relief officials and representatives from both rebel groups should visit the scene and make an assessment. They flew up to Loki and started driving north, through the badlands of southernmost Sudan.

Once they crossed into Equatoria, they found themselves driving through a sea of Dinka refugees, all shrieking and wailing about what the Nuer had done at Bor. As their Landcruiser approached Jemeza, a village south of Bor, a silence fell. Then they saw the bodies. Some were hanging from trees. Others lay beside the dirt road. They saw three children, tied together and shot through the heads. They saw disembowelled women. Scott- Villiers took pictures. They kept driving. In Bor, the huts were still smouldering. The UN house stank - a soldier's body was rotting inside. They noticed Nuer government ID cards spilled on the floor. Garang's forces had just retaken the town. The relief officials could hear gunfire. An SPLA-Mainstream soldier approached them menacingly. "This is what you lot have caused," he said. They turned around and drove back to Loki.

Scott-Villiers was shaken. In Nairobi, another Operation Lifeline official took him aside and suggested that he take a break from Sudan. "You must not become part of it," he warned. Patta Scott-Villiers took one look at her husband's pictures and was afraid. She felt that they had been in the presence of evil in Nasir. "I felt that anyone associated with it was going to be in moral danger," she said later. After a few days, Scott-Villiers took his pictures to Emma, who was at Sally Dudmesh's house in Nairobi, waiting for news from Bor. "Just have a look at these," he said, tossing the black-and-white photos onto a table. Taut as a cat, Emma snatched them up. They showed a dead child, buzzards eating the naked body of a man, Dinka streaming down the road.

"What are these?" she said impatiently. "Was it a victory?"

It was not a victory. It came to be known as the Bor Massacre. Amnesty International later estimated that 2,000 people died in nearly two weeks of killing. Looking back, most observers agree that the massacre was the point at which Riek and Lam's rebellion turned irrevocably tribal. Why did they let it happen? "It got out of control," was the explanation Riek offered.

I HAVE some pictures of Emma in Nasir, taken by a British friend in 1992. In one, Emma stands outside a mud tukul, squinting at the sun. She's wearing a sleeveless black lace shirt, a long skirt and flip-flops. Her dark hair is stylishly cut; her long hands are clasped behind her back. In another, Emma is sitting inside the hut on an iron bedstead. A mosquito net hangs over the bed, and, behind it, you can see her clothes hanging on a line strung across the hut. The walls are painted black, white and brown, with African animals, human figures and geometric shapes. The third picture is the only one to include Riek. He and Emma are sitting in front of a table covered with ledgers, papers and airmail envelopes. Riek is looking straight at the camera, dressed like a cartoon African dictator in military fatigues with giant epaulettes and a bright red beret. Emma leans on the table, looking down, half-smiling at something you can't see.

She looks a little self-conscious, as if she were posing on the set of a movie. But people who visited her in Nasir say she took her queenly position quite seriously. Sally Dudmesh managed to fly up with the UN not long after Emma and Riek were married. "She was very busy with what he was doing and it was just horrible there," she said. "There were mosquitoes everywhere. The only thing to look at was that great river, and you couldn't even swim in it because of the crocodiles.

"But she didn't mind at all. She would never ask for a single thing. She would never send for shampoo. She would live on rice and boiled fish for months on end without complaining. Then it was like she had two lives because she would come out of these swamps of hell, walk into my wardrobe in Nairobi and come out looking like something out of Vogue."

Emma seemed to revel in her role as the warlord's consort. There was talk of Lady Macbeth. When Garang's fighters began raiding Nuerland in retaliation for Bor, Riek tried to persuade Emma to go to Nairobi because, in a radio broadcast, Garang had blamed the split on Emma. Now, she was a target. She refused to leave Riek, but did begin travelling everywhere with a 7ft bodyguard named "Forty-Six" - after a certain machine-gun he liked to use.

In June 1992, the journalist Tarquin Hall went to Sudan to write about Emma. Hall had been present when Emma and Riek presided - "like royalty at Ascot" - over celebrations to mark the liberation of Nasir three years earlier. "Everywhere we went the Sudanese seemed happy to see Emma even though she had learned little of their language," he wrote. "In villages, people would run up to her car as she drove past, bringing presents and seeking her advice."

When Hall asked her how she felt about Riek's role as a military man who made decisions to have people killed, she replied, "I don't think Riek is in the war because he loves it or because he loves fighting ... Riek has chosen it because of a principle, as a means to an end."

Emma's former colleagues had more difficulty discerning exactly what principle Riek was fighting for. They began to say that Riek was no better than Garang - and maybe worse, because of the damage he had done to the cause of southern unity. The tension grew between them and Emma. The UN banned her from its flights after Garang's faction complained. There was no way the UN could justify letting the white wife of one rebel leader on its flights while banning the families of others. But once again Emma wouldn't see it. "The UN refuses to allow me to fly on their planes for some unknown reason," she wrote to her friend Emma Marion.

People who challenged Emma about the atrocities learned to drop the subject or risk losing her friendship. But if her alienation from the humanitarians bothered her, she didn't show it. "I am so happy," she told Tarquin Hall. "Whatever happens, I'm glad that I followed my instinct, married Riek and came to live in Nasir. I have no regrets."

TOWARDS the end of 1992, Riek and Emma made a pilgrimage through the swamps on foot to the town of Ayod, to a ceremony in which Riek would be given a leopard skin, a Nuer symbol of divinity. This would give him the spiritual authority to absolve men of murder and to settle blood feuds. From the town of Waat, where they started, it was 80 miles to Ayod. The trip took five days. Sometimes they walked through chest-deep water. Riek's men offered to carry Emma, but she insisted on walking. Emma later dubbed the area between Waat, Ayod and Kongor "the Hunger Triangle", and the media picked up on it. The war, at this time, had become a hopeless three-sided affair. There was so much fighting that Operation Lifeline shut down. People were dying of hunger and sickness. Nearby, at Nuerland's most sacred shrine, the giant earth Mound of Ngundeng, tribesmen offered prayers for victory.

For a moment, it seemed as if they had been heard. In October, the prophet Wut Nyang and his followers attacked the government garrison town of Malakal, a hundred miles to the west of Nasir, on the Nile. When Riek learned that they had overrun a few suburbs, he was overjoyed. In a delirious press release, he announced that his forces had captured Malakal, a town of more than 10,000 people. But government forces swiftly drove Wut Nyang and his army away, reportedly slaughtering hundreds of Nuer civilians in revenge. "By then I think even Emma realised how weak Riek was," said Lam.

Riek and Emma were still in Waat when, in January, an incident took place that Emma could not ignore. Lam says that Riek had begun to fear that his underlings were plotting against him. It's certain, at least, that the Nuer had begun feuding among themselves, and that Riek's lieutenants were beginning to divide along lines of kinship. One officer, Hakim Gabriel Aluong, fell foul of the others in some murky dispute and was dragged away in Emma's presence to be shot. Riek's men paid no attention when she pleaded for Hakim's life. "Emma came [to Nairobi] and she was very angry," recalled Lam. "She talked to everyone about it. Now it was really in front of her eyes. But she didn't blame Riek. She said it was the officers."

She was admitted to Nairobi Hospital, feverish with hepatitis and malaria. But after a few weeks, she left the hospital and threw herself into the preparations for a big political meeting that Riek planned to hold in the Dinka settlement of Panyagor. The plan, she told journalists, was to hold a rally with all the Nasir leaders, to show the Dinka and the other tribes that the struggle within the SPLA was not tribal, but about principles. Before the war, Panyagor had been the site of a Western development project: the Dinka were there because it had an airstrip, and the UN offered food. A few weeks earlier, the US Center for Disease Control had reported that rates of malnutrition in Panyagor were "among the highest ever recorded". A Frenchman named Jean Francois Darcq was responsible for feeding the people in Panyagor. On 26 March, Darcq and several thousand others in Panyagor listened to Riek and his comrades appealing to the Dinka to rise against Garang.

At six the next morning, Darcq was in the UN's storehouse, talking on the radio. When he heard shooting, he thought that Riek's forces were holding a parade. Then the UN watchman told him they were under attack by Garang's SPLA. The watchman ran, but Darcq stayed in the brick storehouse. When the mortars and rocket-propelled grenades died down, he peeked outside. People were running and falling and lying on the ground bleeding. A couple of Garang's young fighters appeared with rifles. They ordered Darcq to take off his shirt, trousers, shoes and socks. They left him with his underpants. Darcq knew what this meant. "They were shooting the guys whose underwear they had taken off. Because they don't like to dirty them with blood. So then I thought that they would not kill me."

A long, terrifying day passed in which Darcq was shot at and forced to run through the bush before Riek's forces recaptured the town and released him. Emma came limping in along with Riek's soldiers. She later said she had hidden under an overturned cupboard until Forty-Six, her bodyguard, rescued her. She ran from the gun battle barefoot through the thorn scrub, lacerating her feet. One of the Nasir group's most venerable supporters, an elderly politician who had once served as Sudan's minister of sport, couldn't keep up. When he fell, Garang's fighters shot him in the back. Garang's men caught Emma's dog and beat it, calling it "Emma". For half of the day Emma believed that Riek too had been killed.

Emma's narrow escape seemed to sober her. She had spent all her savings; she and Riek owed money to everyone. The electricity and the telephones were always off at the office that Riek's faction kept in Nairobi, even though the UN gave it money to pay the bills. In London she had met a literary agent who was interested in her story. She started writing her autobiography: Wedded to the Cause. Bit by bit, crumpled sheets began to arrive in London, after a circuitous journey involving friends and friends of friends. The first chapter described her departure from Panyagor.

"I climbed in and bent to kiss Riek goodbye at the door. The door closed, the engine started and we sped down the airstrip and turned sharply away from the fighting. I looked down and saw Riek and his men watch us go until they became mere dots on the earth's surface. Part of my heart remained behind with Riek. As we soared up, as if magically lifted from hell, the vastness of this great flat land overwhelmed me ... Unstoppable tears poured down my cheeks, washing away all the shock, the fear and the grief. I grieved for those who had died and those who would die in this endless struggle."

She had always wanted to have a child, and started taking fertility pills. In the summer of 1993 she became pregnant.

RIEK AND Lam continued their secret talks with Khartoum. In September 1993, Emma chartered a plane so that she and Riek could pick up Lam from one meeting with government officials in the Shilluk town of Tonga. When they returned to Nairobi, they were put up at the InterContinental Hotel by Tiny Rowland. In late October, the US government invited Riek and Garang to see if the two rebel leaders couldn't patch up their differences in Washington. Emma stayed behind at the InterContinental - because of her pregnancy, she had been advised not to fly. After the talks in Washington collapsed, she phoned me in Atlanta, where I was working, urging me to see Riek and get his side of the story. She sounded worried, but when I saw Riek he was suave and relaxed, patiently recounting the obscure affronts that made it impossible for him to sign an agreement with Garang.

Riek stopped in London on his way home to see Angelina and the children. When he returned to Nairobi, Emma had found a house, again courtesy of Tiny Rowland. It was a white stucco bungalow off Riverside Drive, a smart area where the Kenyan bigwigs and Western diplomats live. To Emma's brother Johnny, and her sister Jenny, who arrived in November for their first visit to Africa, she had never seemed happier.

Lam Akol believes that it was during this period that Riek gave orders for the arrest of Lul, the lecherous education coordinator I had met back in Nasir. Gordon Kong Chuol was in charge in Nasir: he accused Lul and 13 others of plotting to bring a well-known Nuer politician back from exile in Sweden to overthrow Rick. A few weeks later, Lam and a Nuer lawyer, one of Riek's lieutenants, heard that Lul was dead. They asked Riek about it. Riek said that Lul had died of typhoid. The lawyer was suspicious. He went to Nasir to investigate. There he heard another story. Every evening at 7pm, he was told, the prisoners were taken out of their huts and beaten, one by one. One night, Lul was not brought back until after midnight. He was nearly unconscious and vomiting blood. That night, he died.

When the lawyer returned with his report, Riek swore that he hadn't known that Lul was tortured to death. He said he would court-martial Gordon. But nothing much happened. Gordon continued to reign in Nasir, undisturbed.

On 24 November 1993, Emma was busy writing a proposal for the UN to finance a new aid group run by southern Sudanese women. "Womenaid," Emma typed, "wishes to help people displaced by war and famine to help themselves and their families." She was alone in the house off Riverside Drive. Her brother and sister had decided to spend an extra day on the coast. Riek was away at a meeting. She planned to meet her friends Sally Dudmesh and Willy Knocker for dinner in the Nairobi suburb called Karen. Midway through a list of Womenaid's proposed "small income- generating projects" - restaurant, $5,000; tea shop, $3,000; vegetable gardens, $3,000 - she stored the document and turned off her computer. For some reason, Forty-Six wasn't around, so she borrowed a neighbour's Landcruiser and drove off. She was five months pregnant. She didn't bother with a seat belt. Hardly anyone in Africa ever does.

When she reached the intersection with James Gichuru Road, she slowed, then started to cross. Naturally, there were no traffic lights, and Emma didn't see one of Nairobi's notorious little private buses, a matatu, barrelling down the road towards her. When the matatu hit the Landcruiser, she was thrown through the window. The car rolled on top of her.

"My baby! My baby!" she was crying when the first Kenyan passers-by reached her. She died on the way to Nairobi Hospital.

FOR A few years after Emma died, Riek Machar seemed to avoid talking about her. Emma's mother mailed him a new Church of England diary every year at Christmas, but he didn't write back. Maybe he was busy - he had a war to fight, after all - or maybe, as he told me, the subject was too painful. At first he didn't answer my faxes and letters either. But in April 1997 he signed a peace agreement with the hated Islamic regime in the north. Many southerners branded him a traitor. Desperate for any favourable publicity, his supporters pushed him to see me. I flew to Khartoum in June.

The government had lent Riek one of those big, half-empty stucco villas that drowse along the avenues of old Khartoum. Human-rights groups say the Sudanese security forces torture their opponents in some of these decaying mansions, or "ghost houses".

When we drove up to Riek's big brown villa on University Avenue, my Arab taxi driver clucked disapprovingly at the teenage Nuer boys swaggering around the grounds in their startlingly green fatigues. At 8am it was so hot outside that sand blowing in my face felt like a dirty flame. The boys grinned sweetly, hurrying me into the house and up an unlit staircase. "Dr Riek is expecting you," they sang. They flung open a door, and I walked into a room dominated by a giant bed.

Riek came forward with a dazzling white grin and offered me a chair at the foot of the bed. One aspect of Sudan that might have attracted Emma was the sheer height of its people: it was the one place where she wouldn't have felt gangly. Riek is nearly 7ft tall, in his mid-forties, not gaunt like most Nuer, but rather fleshy, with small black eyes. He was wearing smartly pressed blue jeans, a matching denim shirt, new shoes and socks. He fetched a Coke for me out of a sweaty little refrigerator by the wall. His voice was thick and sweet. I remembered something a Washington negotiator once told me how he got the feeling that Riek was either a very nice guy or a very effective murderer.

He sat down opposite me and we talked for a long while before I got up the nerve to ask him about Emma. We talked about his upbringing: born in 1952, he was the 26th child of a headman in Ler. I've seen photos of Ler. It's a village of mud houses and cattle byres with conical thatched roofs. When Riek was growing up there was no plumbing, no electricity, no doctor, and no secondary school - only the civil war. It's the same today.

Not many people from Ler go to universities overseas. Riek said he owes his unusual education to his mother. Illiterate herself, she was the third of his father's five wives. But she had a cousin who was one of the first southerners to attend university, and developed a fierce ambition for her sons to do the same. Riek became one of the first hundred southerners admitted to the University of Khartoum after the war, and his brother ultimately became a professor of veterinary medicine. Out of their father's 31 children, only Riek and his brother went to school.

I asked him why he was so willing to fight - why peace wasn't more precious to him. "One individual success, to us, was nothing," he said. "We southerners are just downtrodden."

Finally we reached the year 1989, when he met Emma. He started to tell me about their first encounter, then stopped. I was astonished to see his face pucker up in an expression almost like a pout. He cocked his head at me. His voice turned sentimental. "Do I have to?" he said coyly.

What could I say? I said nothing.

He began speaking in a more normal voice. A schoolfriend had introduced them, he said. He was in Nairobi on a break after five years in the bush, most recently as the commander of Upper Nile province. He didn't say that it was "love at first sight"; merely that he was attracted by her interest in education. He told me about her bold car journey to see him in Nasir in 1991.

"Were you flattered by that?" I asked.

"Beyond flattered," he said huskily.

I sat up in my chair.

"She - there were no inhibitions on her side," he added.

"I see," I said. I was afraid that I might blush or burst out laughing. I thought about the answers others had given when I asked them what had attracted Emma to Riek. "She just adored being with him," said Sally Dudmesh. "He was a big sexual powerhouse," said an American journalist who knew them both.

A gaggle of Riek's advisers came into the room and sat down on a sofa next to me. The advisers were in Khartoum to draft the provisions that would, supposedly, make Riek's peace agreement part of Sudan's constitution. (Three months later, Riek and the government were still arguing.) They needed Riek's approval for their latest work. While Riek tapped away on his laptop computer, I looked out the window. Outside on the grass, two soldiers armed with automatic rifles lolled under red carpets strung up like an Arab tent. I asked the advisers about the villa's age.

"I think it was built in the 1970s," said one man.

A sad-eyed Nuer, one I had met before, corrected him.

"No, it was built earlier than that, because this is where Numeiri held the officers who tried to overthrow him in 1971," he said. "This is where he had them executed, right in this house." We looked at each other. The air-conditioner in the window droned feebly. I apologised for bringing up painful subjects.

"No, it's OK," said Riek. "It's been a day of remembrance." And it was over. Riek stood up. I could see that his mind was already with the chattering men waiting for him on the faded couches in the hall. I went back to my hotel room and lay in the gloom, watching the ceiling fan go round.

IN LONDON I met Emma's brother Johnny for a drink. He helps produce television comedies at studios in Covent Garden. It was a warm summer evening. The pubs and restaurants overflowed with young people, their laughter rising up to the pale lavender sky. We found a table in a crowded brasserie. Johnny is slight, with sandy hair and wire-rimmed glasses. He has his sister's fine features, and her silvery charm.

"I still hear her voice sometimes," he said. I heard it, too.

"It wasn't until I was at the funeral that I realised she had made such an impact," he said. "You know, after she died, her friends came to me in Nairobi, and they said, 'You'd better get Nairobi Cathedral for the funeral.' I told them, 'You must be mad.' Because, you know, if I died, I really don't know if I could fill a village church. But we did get the cathedral and when we went there it was packed to the rafters. Then we took her body up to Ler, where Riek is from. She's buried there. It's quite a pretty place, but, my God, the sun! And people had walked for days to get there. When our plane landed Riek had to get a megaphone to get them to step back so we could get off. There were thousands of people - thousands. We were the only white people there. They were all rushing forward. We thought we were going to end up in the grave ourselves."

He laughed. Then he said: "Emma wasn't out to better herself. When I think about her, I feel a bit guilty about my life. I'm doing something really selfish. I'm not bettering anyone."

There it was again: the noble cause, the great saving illusion. I didn't say anything. I thought of Somalia and Sudan, of all that vainglorious rhetoric about saving a nation by throwing bags of food at it. I remember how Emma laughed at the aid workers in Sudan who fondly imagined that they were in charge of events. At least Emma took Africa seriously enough to see how little aid could accomplish.

At home in Atlanta, I called Tiny Rowland in England to ask him if he had known Emma. It took him a few moments to remember. Then it clicked. "Yes, of course I met her," he said. "Yes. And when she died Riek was in a dreadful mess."

How important a figure was she? I asked him. He paused. "My dear," he said. "She was a white woman, a married white woman. I'm sure she helped him enormously. But in terms of Africa, she didn't play a role."

It struck me that the saddest thing about Emma was the waste of it all. She had beauty, passion, talent, a radiant spirit. Yes, she had been up to her neck in horrors. But the horrors would have happened even if she hadn't been there. Certainly they continued without her. I don't know if she helped many Sudanese. Once she surrendered so wholeheartedly to her intoxication with the place, she might have harmed more people than she helped. She never appears to have seen the damage she did to her best self when she followed Riek into the wilderness of that war. But the lure was too powerful for her to resist. She had grandeur. She was not ordinary. She loved her fate.

A longer version of this article appears in the new issue of Granta magazine, 'Unbelievable', available now in bookshops, price pounds 7.99, or direct from Granta for pounds 6.99 (freecall 0500 004033 for details).