As the largest tribal group in the Amazon, there were around 38,000 Yanomami still living in the rainforest in 2020. Their traditional homelands were in the mountainous highlands of Brazil and Venezuela, away from the big rivers and relatively inaccessible. For this reason they were spared the ravaging effects of the previously unknown diseases brought by the Spanish conquistadors to South America during the seventeenth century, which wiped out many of the riverine tribes completely. Since then their territories have expanded into the lower valleys, but despite this, until recent times the only contact the Yanomami have had with outsiders had been through the occasional visits of scientists or missionaries. A report in June 2015 states that the Yanomami and other tribes are having to protest against the incursion into their land of violent mining gangs. Their land is being ravaged, and their water is being poisoned. Although the Venezuelan government recognises the Yanomani rights to their ancestral lands, they have not protected them from the miners and are planning to open up some of their land to mining.
Back in 1985, a gold-rush on Yanomami lands in Brazil led to the influx of tens of thousands of miners and prospectors, overwhelming the small populations of local people. So far the Yanomami have been able to maintain their traditional customs, despite outside influences. After world-wide protest at the harsh treatment of the Yanomami, the Brazilian government was forced to grant the Yanomami 94,000 square kilometres of territory, an area larger than Scotland, in 1991. As has been noted above, even small groups need very large areas of territory in order to provide for themselves. The Yanomami know that if their population density increases, they will start to overuse their resources.
Despite having the supposed protection of the Brazilian government, garimpeiros - illegal gold miners - continue to prospect on Yanomami lands. They have brought with them diseases that are either lethal or very difficult to control among the Yanomami.