Gentleman thrillseeker: How Wilfred Thesiger blazed a trail across Africa and Arabia

Switch on the television any night of the week, and you will see modern explorers travelling the globe. Though he only died in 2003, Sir Wilfred Thesiger belonged to another era. Described by the travel writer Eric Newby as a "throwback" to the golden age of 19th-century exploration and travel in Africa and the East, Thesiger was a self-confessed romantic and traditionalist, who, in his own words, "cherished the past, felt out of step with the present and dreaded the future". For most of his life, Thesiger lived in separate worlds, each with its distinctive dress code. "In London, I'd put on a dark suit and lunch at the Travellers [Club]. In Iraq, I'd take my tweed coat and dish-dasha and go off down to the Marshes."

Thesiger's childhood experiences of Ethiopia's "gorgeous barbarity" gave him a desire to emulate the deeds of great Victorian explorers and hunter-naturalists. He felt most at ease among tribal peoples, to whom family dignity and loyalty were essentials of everyday existence; whose traditions had not been subverted by Western materialism and technology. He saw, and had the skill to communicate, the essence of alternative cultures. Thesiger travelled for pleasure, both as a way of life, and as a recreation. He valued hard travel for itself, not simply as an adjunct to administration, scientific research or travel writing.

Aristocratic by birth, educated at Eton and Oxford, he was independent, but never wealthy. Thesiger did not fit the role of an academic or scientific observer, amateur adventurer or aimless wanderer. His privileged background gave him a profound sense of duty, nationality and social status, and useful habits of delegations and dominance, he found in degrees mirrored by tribes with whom he associated. In Arabian Sands and other books, he defined his motives for travel as "the lure of the unknown", "winning distinction" for his journeys, and searching for "peace of mind" among races other than his own. Thesiger was both an establishment figure and a misfit, a reactionary and a rebel. By the age of 14, he had already determined to live amid "colour and savagery".

The eldest of four brothers, Wilfred Patrick Thesiger was born on 3 June 1910 in a mud hut in Addis Ababa, Ethiopia, where his father was Minister in charge of the British Legation. His grandfather, Lord Chelmsford, commanded the British force during the Zulu war in 1879, when 1,300 of his men were massacred on the slopes of Isandlwana. In his family, his father's generation included a viceroy, an admiral and a Lord of Appeal. Sir Wilfred's cousin, the actor Ernest Thesiger, starred in the 1935 cult horror film, The Bride of Frankenstein.

Thesiger felt convinced that his nine years' upbringing in Abyssinia, as Ethiopia was then known, crucially influenced the whole of his life. Thesiger's father and his staff enthralled the boy with tales of tribal wars and lion hunts. He remembered watching his father shoot an oryx; herdsmen and camels at waterholes; priests with silver drums dancing at Epiphany; bloodstained troops led by the Abyssinian regent, Ras Tafari, frenzied with excitement after their victory at nearby Sagale, which crushed the revolution in 1916. That same year Wilfred's uncle, Frederic Chelmsford, was installed as Viceroy of India.

Even as a small boy, he had been conscious of the immense power and spectacle of Empire; of ancestors and relatives, honoured as servants of the Crown.

Thesiger's father died soon after the family left Abyssinia in 1919 for England, a country as unreal to Wilfred as his adventures appeared to English children. Abused by his prep school headmaster, shunned by peers as a freak and a liar, Thesiger fared better at Eton where, despite an awkward, thuggish demeanour, he made lasting friendships. At Oxford he boxed for the university side, paid frequent visits to his new literary hero, John Buchan, and read modern history.

In 1930 Ras Tafari issued Thesiger with the only private invitation to his coronation as the Emperor Haile Selassie. At Addis Ababa he saw Evelyn Waugh whom he disliked; but whose portrayal of Oxford decadence in Brideshead Revisited echoes Thesiger's suppressed nostalgia for lost emotional relationships, revived years later in The Life of My Choice, his best-selling autobiography.

After the coronation, Thesiger hunted big game in the Danakil (Afar) country, following the Awash river whose unknown end he had determined, meanwhile, to discover. During the decisive month he spent there, he found excitement and danger from hostile tribes and wild animals; "with no possibility of getting help ... men's lives, had depended on my judgement", he wrote, as a 20-year-old.

Thesiger continued to explore the Awash river in 1933-34, and became the first European to cross Aussa, a forbidden territory ruled by a xenophobic sultan. As he journeyed, he still travelled in the style of "an Englishman in Africa", eating and sleeping apart from the other members of his caravan. Thesiger's activities set a pattern for later journeys in Africa, Arabia, the Middle East and western Asia.

Like the classic Victorian explorers, he drew maps and collected specimens of plants, mammals, and birds; he kept meticulous diaries, noted Danakil customs and took a great many photographs. While he claimed not to have extensive knowledge of anthropology, botany, ethnology, geology, geography, ornithology or zoology, these featured in most of his future travels. In 1955 and 1977 he took part, but only briefly, in larger scientific expeditions. Otherwise Thesiger did all his journeys on foot, using baggage animals, such as camels or donkeys – alone, except for a few local tribesmen. Journeying in "the tradition of the past", by 1970 he had walked for 100,000 miles and, quite literally worn out the cartilage in both knees.

From 1935-1940, Thesiger served as an assistant District Commissioner with the Sudan Political Service. In northern Darfur, he learnt to ride camels and above all to regard his followers as companions rather than servants. This was a crucial transition which enabled him to get on closer terms with his men and ultimately to be more than an outsider and spectator. Yet while Thesiger treated the men closest to him with sympathy and respect, some were bound to him by obligations (such as a Sudanese gunbearer whom Thesiger freed from jail), others (like certain Kenya tribespeople) for financial support. According to Thesiger's friends, the line dividing companion and servant was, however, sometimes blurred.

People mattered to Thesiger far more than exploration or travel. In the Sudan he shot 70 lions, saving many herdsmen's lives, but he later conceded that this figure did seem "appalling". His 2,000-mile return journey across the Sahara to Tibesti in 1938 was the first of its kind from the east. Giving his mother the news, he wrote with quiet pride that "it is not easy to be the first Englishman nowadays".

During the Abyssinian campaign in the Second World War, Thesiger served under Orde Wingate and earned a Distinguished Service Order for capturing Agibar fort and its garrison of 2,500 Italians. After active service with Special Operations Executive in Syria and the Special Air Service in North Africa, he returned for a year to Ethiopia at the Emperor's request. A chance encounter at Addis Ababa gave Thesiger the opportunity to fulfil his supreme, remaining ambition of travelling in the Empty Quarter: the vast, largely unexplored sand desert in southern Arabia.

Thesiger's fascination with the desert Arabs was stirred by reading T E Lawrence, and books by the explorers Bartram Thomas and Harry St John Philby who crossed the Empty Quarter in the 1930s. Searching for locust outbreak-centres gave Thesiger access to remote areas and an introduction to the tribes. In 1946-48, he crossed the Empty Quarter twice. Apart from the intense hardships, continual hunger and thirst and the risk that his party would be murdered by fanatical tribesmen, Thesiger strove to accustom himself to his companions' ways, trying to match their standards of endurance, generosity and loyalty. In Arabia, he added to earlier feats of exploration by surmounting the 700-ft high dune-chain, Uruq al Shaiba, being the first outsider to sight the Liwa oasis, south of Abu Dhabi, and first to view the fabled quicksands known as Umm al Samim "Mother of Poison" which bordered Oman. Thesiger's reward for his crucifying journeys had been a drink of "clean nearly tasteless" water. Without the comradeship of Bin Kabina, Bin Ghabaisha, and other Bedu who went with him, Thesiger insisted that these journeys across Arabia would have been "a meaningless penance".

Seven years, 1950-58, living among the Marsh Arabs in southern Iraq, contrasted Thesiger's "five most memorable years" in desert Arabia. Every summer he trekked across the Hindu Kush, the Karakorams or Morocco. In 1959-60, two journeys in Ethiopia preceded the first of many camel-safaris to Lake Turkana, in northern Kenya. Based at Maralal, Thesiger lived and travelled in Kenya for much of the next thirty-five years.

Since 1930 Thesiger had documented his journeys in photographs, diaries, and letters to his family. Many of his finest photographs were taken, after 1945, in Arabia and Iraq; he took thousands more, just as fine, in the mountains of Asia, Morocco, Kenya and Tanzania.

Thesiger's photographs have long been regarded as works of art in their own right; they also preserve a unique and imperishable record of vanishing tribal societies. They illustrate all of Thesiger's books, starting with Arabian Sands (1959) and The Marsh Arabs (1964), whose huge critical and popular success helped to recreate Thesiger the reticent, reserved gentleman traveller and explorer as a living legend.

Yet the inevitable pleasure Wilfred Thesiger derived from worldwide acclaim was tempered, and given a subtler perspective, by his often-repeated remark – that his books and photographs had been merely the "by-products" of his life and travels.

Wilfred Thesiger in Africa is published by HarperPress (£25). To order a copy for the special price of £22.50 (free P&P) call Independent Books Direct on 08430 600 030, or visit www.independentbooksdirect.co.uk