Sitting in one of the world's most remote and inhospitable landscapes, Jonathan Mazower and his trusty laptop computer appear in stark contrast to their surroundings.

Far from his home and his two young sons in Cleveley, near Enstone, Mr Mazower, however, is helping to make history.

The research coordinator at Survival International, the worldwide organisation supporting tribal peoples, Mr Mazower, 39, has just returned from the Central Kalahari Game Reserve, where he visited Gana and Gwi Bushmen who have been evicted from their ancestral desert land by the government.

Many of these displaced people are now living in resettlement camps, but Survival is campaigning for them to be allowed home, and is supporting them in a court case against the Botswanan government - the longest, most costly and highest-profile in the country's history.

"I was in the game reserve for about three and half weeks," said Mr Mazower.

"It was my first trip to Botswana and I was there principally to meet and talk to the Bushmen and their families and also to help their local organisation, The First People of the Kalihari, use computers to record the Bushmen's names and photographs, to assist in their court case."

No stranger to persecution, the Bushmen had their homelands invaded by cattle-herding Bantu tribes from about 1,500 years ago, and by white colonists over the last few hundred years.

But as well as this, they have now been evicted from their ancestral lands, and suffered a massive though unspoken genocide, which has reduced their numbers from several million to 100,000.

Today, following the government evictions, only around 30 Bushmen are still living in the central reserve and many tribes have no land rights at all - the Gana and Gwi tribes are among the most persecuted.

Mr Mazower said: "I spent most of the time travelling around the three main resettlement camps, where these people have been placed.

"Whereas, in the reserve, they live in small, scattered villages, across a wide expanse of desert, in the camps, there are hundreds of people thrust together and as a result there are many problems with alcohol and Aids.

"Whereas they are used to hunting and gathering for a living, in the camps they are crammed together, in an environment where all the game has been hunted out and the landscape is degraded.

"There is no way they can support themselves: there are no jobs and all they have to live on are the monthly deprivation rations the government provides."

The Bushmen are the oldest inhabitants of southern Africa, having lived there for at least 20,000 years.

Their daily diet has always consisted of the fruits, nuts and roots which they seek out in the desert, and they make their own temporary homes from wood that they gather.

They speak a variety of languages, all of which incorporate 'click' sounds, represented in writing by symbols such as ! or /.

But whereas the Bushmen want to continue living in the Kalahari, the government argues they no longer live a traditional hunting existence and keep domesticated animals in the reserve something it says is to the detriment of the wildlife and should not be allowed.

"The Bushmen have had no choice but to leave," said Mr Mazower.

"I spoke to hundreds and asked them whether they truly wanted to return to the reserve and the majority said yes, but it all hinges on the result of their case, which has been taken on by one British and one African lawyer.

"It was a very depressing trip, but also, in an odd way, it was also very encouraging," he added.

"I saw a Bushman female of about 35, who was dying of TB and Aids and has already lost her sister to Aids. She told me she wanted to be in the home of her ancestors when she died.

"I also spoke to a healer woman who said she could no longer heal her tribesmen because she was in a place with no knowledge of the roots and plants she needed to make her medicines.

"But I was also deeply encouraged by how many of these people still had a burning desire to return home.

"Returning to Oxfordshire I was struck by the order of things, by the way that all the land is owned by someone - a complete contrast to the wide expanses of the Kalahari desert.

"I also looked at our typical house and my two boys' many toys and realised just how little the Bushmen have, but also how little they actually need to live in contentment in their homeland.

"We at Survival will continue with our work to campaign on behalf of the Bushmen tribes and highlight their plight, and hopefully, in a couple of months, when the judge makes his ruling, these people will at last be able to return to their rightful home."