[a Brazilian people who were] were gradually expelled by European colonists westward beyond the Serra dos Aimorés into Minas Gerais. It was in the latter district that at the close of the 18th century they came into collision with the Europeans, who were attracted there by the diamond fields.
At the end of the 19th century many [tribes] still existed, numbering between 13,000 and 14,000 individuals. During the earlier frontier wars of 1790-1820, every effort was made to destroy them. Smallpox was deliberately spread among them; poisoned food was scattered in the forests; by such infamous means, the coast districts about Rio Doce and Belmonte were cleared, and one Portuguese commander boasted that he had either slain with his own hands or ordered to be butchered many hundreds of them
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Botocudos: a wandering wild tribe in the forests of Brazil, near the coast; a very low type of men, and at a very low stage of civilisation; are demon-worshippers, and are said to have no numerals beyond one.*
Rev. James Wood. The Nuttall Encyclopaedia (1907)
*Although this definition is horrible, the quote itself is useful in understanding older European attitudes towards other cultures. It is possible that the mining companies themselves, desiring unfettered access to the diamond mines, helped to foment these prejudices to justify the extirpation of this race.