Can you be sure of Ken Saro-Wiwa?

When the Nigerian dissident and eight others were hanged a year ago, the West cast him as a hero and Shell as the villain.

A year ago this weekend, Ken Saro-Wiwa and eight other Ogoni activists were hanged by the Nigerian authorities. This African, fighting for the rights of the indigenous poor of his minority tribe as, so he claimed, they were raped by the Anglo-Dutch corporation Shell, was the epitome of the Anglicised product of Empire.

Thanks to the interest taken in Saro-Wiwa by organisations such as Greenpeace, The Body Shop and Channel Four Television, his story is well known. He became a founding member of the Movement for the Survival of the Ogoni People (Mosop) in 1990; in 1995, Amnesty International denounced the detentions and trials of Saro-Wiwa and eight other Ogoni detainees as politically motivated. Amnesty deplored the ill-treatment of all the detainees and many of the witnesses at the military-controlled tribunal, and the government's inaction about a spate of security-force killings in Ogoniland in 1993 and 1994, in which hundreds of people died.

Eventually, the campaign forced the oil company Shell, whom Saro-Wiwa accused of implication in the rape of Ogoniland, to undertake the first environmental study of the Niger Delta.

The affair may have made little impression on the Nigerian government, but Shell was shaken to the core. The company's self-esteem, always dangerously inflated, was shattered.

The affable and savvy sitcom writer and campaigner was pipe-smoking and poshly-spoken; he owned a large house in Surrey and sent a son to Eton. He was either a naive hero indifferent to risk, or a flawed maverick who made fatal misjudgements. "Ken was no saint," says Donu Kogbara, a London- based Ogoni journalist friend of his. "He was tremendously charismatic and sometimes very nice," she remembers. But she believes that he lost touch with reality as he was wooed by starry names in Europe and the US.

Ken Saro-Wiwa became a darling of the greener sections of London liberal society, but had been on the federal side during the Biafran civil war, and would thus have been reviled by liberals then. It has been argued that he was a federalist because he thought only a strong state would defend minorities like the Ogoni.

Whatever the case, within Nigeria he is widely believed to have feathered his nest when managing the Niger delta oil port of Bonny during the civil war. It would certainly explain his sudden affluence at that time. If he was a crook, it is no more than Nigerians expect of each other.

Saro-Wiwa finally and fatally enraged his country's military regime by demanding greater autonomy for the people living in a patch of the swampy Niger delta. Given the politics of the country, the more strident of these voices were bound to be silenced. He seems to have been caught out by the military's haphazard alternations between permissiveness and oppression. And he did not help his cause by unleashing undisciplined and deeply disaffected young men on moderate former colleagues in the struggle, four of whom were murdered at a political rally in Ogoniland. Donu Kogbaru believes her own father, one of the moderate leaders, was lucky to escape with his life. "I'm accusing Ken of incitement to murder," Donu Kogbaru insists, when pressed.

Saro-Wiwa certainly believed that the campaign was a useful route to fame and wealth, and told friends that because it had an environmental dimension it pushed all the right buttons in the West. The mystery is how anything that started out as something with at least an element of a scam about it could have turned so darkly tragic.

His campaign was successful because it was directed almost as much at the Shell oil giant as it was at Nigeria's regime. Shell was the obvious target, for an ironic reason, as most of its Nigerian critics freely admit: the oil company is perhaps the most respectable institution in Nigeria.

"We've been here a long time, and we expect to be here a long time," says Brian Anderson, the Nigerian-born white who runs Shell's operations there.

Shell started producing oil from the Niger delta 40 years ago. It was in Nigeria when the place was one of the bright stars of the continent, and expects to be there when and if hope returns. Meanwhile, like any large firm there, it funds armed police seconded from the state for the defence of its people, and necessarily deals with authorities of whom it strongly disapproves. Shell remains adamant that its only purchase of arms has been strictly within government-agreed codes.

Saro-Wiwa realised that Shell was amenable to pressure. It operates as a 30 per cent shareholder, and the largest private shareholder, in a Nigerian joint venture company, Shell Petroleum Development Company (SPDC), alongside Elf and Agip, with the Nigerian state oil company owning 55 per cent. You see the Shell sign everywhere in the delta, but it stands over facilities substantially owned by the Nigerian state, which must put in 55 per cent of the capital expenditure required to keep production flowing - and clean. Shell's biggest problem is in wringing that share from the state.

SPDC produces about a million barrels of oil a day, half the country's total, which in a good year contributes around $9bn dollars to the national exchequer, or three-quarters of the total government revenue (and about a third of the country's GNP). Some of the money is salted away by the country's leadership and their friends. Little of it reaches the delta where it is produced, and where six million people live in a soggy region of farms, forests and swamp about the size of the Republic of Ireland. Even less than its fair share reaches Ogoniland, where half a million of Saro-Wiwa's compatriots live in an area of about 1,000sq km.

The lively Nigerian economist Patrick Utomi once proposed that the oil ought to be given to the ruling elite once and for all: in return, they might give Nigeria back to the people. The Economist Intelligence Unit's regional report notes that the country's economy collapsed during the oil boom: too many important players gave up conventional work and concentrated on trying to cream off a share of the bonanza.

Arguably, none of this is Shell's fault: as Brian Anderson never tires of stressing, 3 per cent of the revenue that SPDC pays the government was supposed to come back to the producing areas. It's a sum close to Shell's 3.2 per cent share of the oil dollar, and is a sliver of the country's average 75 per cent share of the barrel's worth. If the arrangement had worked, the delta might have become a fine area in a fine country.

"The money was not fully spent, and it wasn't wisely spent," Anderson insists, speaking in a code which roughly translates as: the money which isn't stolen is wasted.

A meeting with local chiefs at Sapele township in the north-west of the delta has the erudite community spokesman Vin Kariks Ekariko rattling off a list of health and environmental effects, many of which probably aren't real or could not be caused by the oil industry. After the meeting, and in private, a local chief thanks the Shell people for the scholarships, the education schemes, the community hospitals and all the rest that the company has done locally - and much of it long before the disturbances of the early Nineties. He wants more, and knows that in a better society politics, not begging, would sort things out. He does not say - but it's true - that community leaders are usually as keen to cream off their share of the booty as anyone else.

Shell spends about $20m a year on community projects (and eight times more on environmentally-orientated equipment renewal). "Things are back to front here," says Anderson. "The government's in the oil business and we're in local government." He believes that privatisation is inevitable in the end, and looks forward to it.

Flying over the delta in a Shell helicopter for hundreds of miles, and visiting several noted pollution hotspots as well as observing a dozen or so oil production facilities and, crucially, the water and ground around them - it is hard to see what the environmental fuss has been about. In the delta there are plenty of rivers and creeks where there is an oil sheen. They remain a tiny minority, and the spills may as well have been caused by careless local boatmen as by the oil giant. For the most part, the delta is a vast, watery, deeply verdant region, lying under skies that are ordinarily tropical. Shell occupies a third of 1 per cent of the delta: even if it had devastated that area and 10 times more besides, and it hasn't, the damage would be a fraction of what is routinely claimed by campaigners.

What, then, of the famous flares? First, there are none at all in Ogoniland, where there has been no oil production since 1993, following community disturbances. Elsewhere in the delta, about a hundred flares waste a resource equivalent to a quarter of France's gas demand.

The flares do very little useful work, and they have been castigated by green commentators. Because oil production facilities bring people with money, locals congregate wherever SPDC has kit. Some come to live near flares, which constitute free light and a means of drying root crops such as cassava.

SPDC is committed, and rightly so, to putting out all the flares, if possible by 2008, and about a quarter of them within three years. The latest project to harness around a quarter of the wasted gas involves deals with customers in southern Europe and $5.5bn worth of new plant whose financing was highly problematic, not least because the Nigerian government, already heavily in arrears in its payments to SPDC, had difficulty raising its share.

The scheme has been an on-and-off affair for 20 years, but is now under construction. The deal was agreed in the weeks following Saro-Wiwa's execution, and seemed to some a symbol of Shell's venality.

For Anderson, the position is simple: if Shell pulled out of Nigeria, someone less committed would go in. The gas scheme was a sign of progress, not failure. On the revenue-addicted economy, he comments, "The `curse of oil' is a real issue - but it has brought a lot of good things. I believe very strongly that by being here we offer something for them to choose from." Besides, he adds: "No country in the world has ever left oil in the ground." This is not the observation of an angel, but then there seem to be few angels in this story.

It is hard to imagine any country extracting oil from the delta with less damage. What is harder to sense is whether Shell has been canny - still less, whether it has been at all noble - in its arm-twistings in the Nigerian corridors of power. Certainly Shell could have done better. But would any company have done better than Shell?