"What are you up to?" I asked. He looked at me, then across the valley to a small wood the other side of the stream, and announced solemnly: "I'm going on safari."

He was away all day, returning at dusk covered from head to toe in red dust. In his eye was a tell-tale twinkle. He had not found snakes, or been charged by a lion, or shot any rapids. But in that wood, all alone "on safari", he had had an adventure. And adventure has been one of the most enduring characteristics of the safari, whose origins are centuries old.

The safari began, as the word implies, as an East African phenomenon. Safara is an Arabic verb meaning "to make a journey", with implicit connotations of discovery. From this verb derives the noun safariya - a voyage or expedition - and hence the Swahili synonym safari. But in its modern form the safari, a journey not just in the physical sense but of the imagination, has extended beyond the geographical boundaries of the Swahili-speaking world. Like Africa itself, it has also continually reinvented itself. It is a dynamic entity and incorporates a cocktail of features from its long and exciting history.

Trade was the raison d'ètre of the first safaris. Coastal Arabs and Swahilis, with their distinctive agglomeration of Arab and African blood and culture, traded for centuries with the African interior and the word safari was used to refer not only to the traders' expeditions but also to their huge caravans. Throughout the eighteenth century the prized products sought by the merchants were ivory, rhino horn, and slaves for the Arabian, Indian and Chinese markets.

Most infamous of the slave traders was the legendary Tippu Tib, who established what amounted to a principality among the Manyema tribe to the west of Lake Tanganyika. In the second half of the nineteenth century he became, along with the Omani Sultan of Zanzibar, the apex of a grisly safari business involving Arab potentates, Swahili merchants, African chiefs and Indian money-lenders (as financiers).

In 1890, however, the British established a Protectorate over Zanzibar. Then in 1896 they effectively took control of the Sultan's domains after a thirty-eight minute conflict, cited by the Guinness Book Of Records as the shortest battle in history. Slavery was banned and the connection between the safari and human misery was thankfully severed.

By then new kinds of safaris were coming of age. The expeditions of European naturalists, such as Burchell and Harry Johnston, and hunters like Cornwallis Harris and Selous, were primarily interested in Africa's wildlife. With the increasing realisation by both naturalists and hunters that this was a finite resource, the first seeds of a conservation ethic were sown. Thus, just as the trading safari had altered, so too did the hunting safari as its practitioners became hunter/naturalists and respected experts in bush lore.

Frederick Courtenay Selous, arguably the greatest white hunter of all time and the man whose name would be adopted by the largest game reserve in the world, was central to this process of change. His first highly-influential book, A Hunter's Wanderings In Africa, was published in 1881 and thrilled readers in Europe. Although today's conservationists would regard the size of his lifetime "bag" with horror, he introduced the peculiarly British concept of "sportsmanship" to hunting as well as encouraging a profound respect for Africa's natural splendours.

Sportsmanship had been most conspicuously absent from the safaris of both Boer hunters, who had largely denuded the Cape Province of game as early as 1810, and African hunters armed by Arab merchants, who by 1850 were killing 30,000 elephant a year in East Africa. Within thirty years of the publication of Selous' book, the first game control laws were established in almost all African countries.

Just as Selous had succeeded in bringing the thrills of a life in the African bush to a rapt European audience, so too did the novels of Rider Haggard. His first blockbuster, King Solomon's Mines, was published in 1875 and its hero, Allan Quatermain, was reputedly based on Selous. Rider Haggard's and Selous' Africa was one of adventure, of wildness, of freedom, of romance. It was thrust firmly into the late Victorian consciousness, influencing generations of young men and imbuing the safari with an irresistible allure.

Like hunters and naturalists, the European explorers also left their mark on the safari. Venturing far into the great "unknown", the expeditions of Stanley and Livingstone, Burton and Speke lasted years and involved the sort of preparations that were more commonly associated with equipping a small army. Many explorers never returned alive, thus demonstrating that risk as well as adventure was an integral part of any safari. The explorers' tales recounted the full range of dangers faced: disease, starvation, searing heat, torrential rain, and attack by wild animals or hostile tribes. The African safari could be a magnificent experience, but it could also be fatal.

No expedition of a European - hunter, naturalist, explorer, conqueror or colonial administrator - would ever have crossed the starting line without the invaluable assistance of another enduring feature of the safari: their indigenous "hosts". A big safari needed headmen to keep order in the ranks, trusted gun-bearers, and a succession of interpreters, guides and cooks to keep the show on the road - as well as porters by the hundred.

Some of the valiant Africans who made exploration possible were almost as well known to European readers as the white explorers themselves. Sidi Bombay (sometime gun-bearer to Speke, Burton and Stanley); Chuma and Susi (the men who carried Livingstone's body thousands of miles to Zanzibar for shipment home for burial in Westminster Abbey in 1874); Mabruki (gun-bearer to Joseph Thomson, Harry Johnston and Frederick Jackson), and Makanjira (gun-bearer to Ewart Grogan on his pioneering first traverse of Africa from Cape Town to Cairo, a journey undertaken to win the hand of his bride) - all were household names in Europe.

By contrast the porters were largely unsung heroes. These were the men who carried loads of up to 60lbs for between ten and fifteen miles per day for the duration of a safari. They shared the hardships - and adventures - of their employers for minimal payment and little of the glory. Some tribes, however, such as the Wanyamwezi, earned a reputation as "specialist" porters which gave them great kudos and meant their services were in constant demand.

In addition to the hunters, naturalists and explorers there were some who went on safari just for the sheer joy of travelling. One of the most extraordinary, and eccentric, of this small band was the Norwegian runner Mensen Ernst. Widely regarded as an "impressive performer", he ran from Paris to Moscow in 14 days in 1832, stopped for a week's sightseeing, and then ran all the way back. This was by way of a warm-up for his African safari. In 1842 he set out from Cairo with the aim of reaching Cape Town, but died of dysentery just 315 miles into his journey. However, his great gusto did not die with him.

Women, in particular, came to be associated with enterprising travel for travel's sake in Africa. Theirs were less intrusive safaris than those of their male counterparts, devoid of the machismo of naming peaks or shooting lions but no less adventurous.

Among the most famous women travellers of a century ago were May French Sheldon and the fifty-year-old Miss Mary Hall. Following the example of Mary Kingsley in West Africa - a woman of whom Kipling said "being human, she must have been afraid of something but one never found out what it was" - Mary French Sheldon, an American, organised and led her own 150-porter caravan to Kilimanjaro in 1891. Mary Hall became the first woman to repeat Ewart Grogan's great trek from Cape to Cairo, a journey she completed in 1907. Female participation in the safari thus became firmly established.

With the dawning of a new century the safari's barometer moved to 'set fair'. The number of European travellers increased following colonisation of the continent and increasing public interest in the hunting safaris of the rich and famous. East Africa remained the home of the safari, partly due to the earlier decimation of wildlife further south, and an entire industry grew up to cater for the every need of American and European clients keen to bag a trophy and experience the thrills of Africa. Skilled hunters like R J Cuninghame and Will Judd, and safari companies like Newland & Tarlton, became world-famous. The concept of the guided safari was born.

But the glamour of the safari, still predominantly a hunting expedition in the first half of this century, came at a price. Theodore Roosevelt's great safari of 1909, which did more than any other to establish Nairobi as the capital of the safari, cost a whopping £15,000. The safari, immortalised with mixed results in various Hollywood productions of the 1950s, thus remained very much the preserve of film stars, millionaires, royalty and aristocrats. Although it survived two world wars, the Great Depression, countless saucy scandals and a continuing diminution in wildlife populations, the safari was not sustainable on such an exclusive basis.

As ever the safari kept one step ahead of crisis by reinventing itself yet again by the middle of this century. The car came to play a key role and portered safaris became less and less common. Hunting was gradually superceded by more pacific forms of safari. Camping safaris grew in popularity. So too did the photographic safari, pioneered in the first decade of the century by Cherry Kearton and E N Buxton and popularised by the five-year film safari of Martin and Osa Johnson in the 1920s (which was funded by George Eastman of Eastman Kodak fame). More unusual were innovations like the balloon safari, which could trace its roots to the rather unsuccessful 1909 "Boyce Balloonograph Expedition" of the eponymous brash Chicago newspaperman.

With such a broad range of types of safari on offer, and greater accessibility as a result of cheaper air travel and rising real incomes in Europe and America, the modern safari was thus able to survive the greatest threat yet - that of the widespread poaching of elephant and rhino in the 1970s.

Safari lodges, both luxurious and simple, continued to multiply even in the worst years of this threat to Africa's wildlife. The popularisation of the safari, and its ever-closer association with conservation, have thus been vital weapons in the war against poachers and unscrupulous politicians, to ensure that Africa's natural resources are protected for future generations.

The safari has therefore come a long way; in a sense it has made a journey of its own. Slave trading and over-zealous hunting are gone; conservation, and the laudable aim of respecting Africa's wildlife resource as one which needs to be carefully handled for the benefit of all races, are hopefully here to stay.

However, certain features of the ever-mutating safari remain constant: the adventure, the sense of freedom, Africa's staggering natural beauty and the crucial participation of Africa's people - both black and white. It also remains a highly personal experience. Long or short, on foot or in a vehicle, in a canoe or in a balloon, it is, and will always remain, something different for every safari-goer. As one wag put it in the 1920s: "it has even been known, in times of grave financial stress, to mean a hurried departure from the haunts where one is known to fresh fields and pastures new".

As we enter the twenty-first century we must hope that the safari, a vibrant and living thing, will continue to surprise us all with its ability to redefine itself. Only by so doing will it remain a constructive force, far removed from its destructive origins in slavery and excessive hunting.

We must hope that the safari, a vibrant and living thing, will continue to surprise us with its ability to redefine itself.

Edward Paice is an historian and author, based in London.

Published in Travel Africa Edition Ten: Winter 1999/2000 Text is subject to Worldwide Copyright (c)