Amazonian Indians from the mist-shrouded mountains of Brazil that inspired Arthur Conan Doyle’s novel The Lost World have come to Europe to lobby the Pope and politicians in a desperate attempt to save their habitat.

The Brazilian Supreme Court will rule in August in a landmark case that pits six powerfully connected rice farmers against about 19,000 Indians. The judgment could open the way for cattle ranchers, farmers and mining companies to move into areas designated as Indian reserves all over the Amazon, reversing years of struggle by tribes and environmentalists.

The case has been brought by the state government of Roraima. It has challenged the federal government over the ratification of an indigenous territory called Raposa Serra do Sol. The state wants it to be reduced and split into islands to “allow economic development”.

Under Brazilian law once an indigenous area has presidential sanction, all nonIndians must leave. After the Raposa Serra do Sol reserve was ratified by President Luiz Inacio Lula da Silva in 2005, a number of small farmers were relocated and compensated. But six families with large rice plantations refused to go, even though the area was already marked out as indigenous land in 1993 when they moved in.

“This is a hugely emblematic case,” said Fiona Watson, campaigns co-ordinator for Survival International, the London-based organisation for tribal peoples. “If the Supreme Court rules against the Indians, we fear it will open up the floodgates. If Raposa falls, I bet the next area will be the Yanomami.”

The Makuxi, Wapixana and three other tribes have fought for decades to get the Brazilian government to protect Raposa Serra do Sol, a spectacularly beautiful area on the borders of Venezuela and Guyana.

Twenty-one of their leaders have been murdered and the last few years have seen frequent onslaughts on their settlements. One attack in May destroyed a bridge linking their villages.

“We cannot let this struggle go to waste,” said Pierlangela Nascimento da Cunha, a Wapixana leader. “Raposa is a paradise of mountains, rivers and waterfalls that is sacred for us; our story is engraved on the stones, and we want to keep it like that for our children.”

She was in London last week to meet MPs and Foreign Office officials together with Jacir Jose de Souza, a Makuxi leader who founded the Indigenous Council of Roraima.

The pair also went to Spain and France and now head for Italy to meet the Pope.

It was da Cunha’s first time outside Amazonia and, sitting opposite the Houses of Parliament, fiddling with her long earring made of macaw feathers, she said she was shocked by the experience.

“Everything is so noisy and so square,” she said. “Where we come from, all huts and villages are round and we have lots of space.”

She was also astonished by travelling on the Tube as in two days she had twice been delayed by bodies under trains. “Who are these people throwing themselves under trains?” she asked. “Don’t they have families?” However, she was eager not to criticise. “This is your way of life, which we respect just as our way should be respected by our government. But there is no one to speak for us in Brazil so we have brought our fight to Europe.”

If the tribes lose the case, they will try to go to the international courts of justice. One reason for the trip is to secure support for this. “The forest, our way of life and livelihoods are being threatened,” said da Cunha. “The rivers where we fish are being drained by the farmers to irrigate their rice and polluted by the herbicides they use.”

But they are up against powerful interests. The leader of the six rice farmers is the mayor of Pacaraima, a city in the northeast of Roraima. When federal police arrived to expel the farmers after the decree, he sent them away.

The tribes believe him to be behind several raids by hooded men armed with knives, guns and clubs such as one on May 5 in which 10 Indians, including children, were wounded and many huts burnt down.

Da Cunha points out that the rice farmers have been offered land in other states. She believes they will not move because they currently pay no taxes.

Local politicians, however, argue that the 4.2m acre Indian reserve takes fertile land needed for the development of Roraima, which has a population of more than 400,000. When it was established the state government announced seven days of mourning and there were angry protests in the state capital.

“What’s at stake is nothing to do with Indians and nonIndians,” said Jose Anchieta Junior, the state governor, “but the interests of the people of Roraima. The crux of the issue is the demarcation of nearly 2m hectares for 17,000 Indians.”

Valeria Carvalho, a Brazilian anthropologist said it was less simple than that. “It seems a lot if you say 100 hectares per person, but it’s a totally different notion of land because of the way they live,” she explained. “They need space for their traditional activities of hunting, moving about and leaving lands fallow.”

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