Euclides da Cunha[1] (Portuguese: [ewˈklidʒiʒ dɐ ˈkũɲɐ], January 20, 1866 – August 15, 1909) was a Brazilian journalist, sociologist and engineer.

Euclides da Cunha was born January 20, 1866, in Cantagalo, Rio de Janeiro, Brazil, where he lived until he was three years old.

In 1897 he accompanied the Army in the Campanha de Canudos, against a rebellious group of peasants under the leadership of Antonio Conselheiro.

[2] In 1903 he was elected to the Academia Brasileira de Letras (Brazilian Academy of Letters) and the Instituto Histórico e Geográfico, the Historical and Geographic Institute[3] In 1904, Da Cunha was employed on a joint Brazilian-Peruvian expedition to determine a border between the countries.

According to historian Susanna B. Hecht, who wrote The Scramble for the Amazon and the Lost Paradise of Euclides Da Cunha, Carlos Scharff, a successful rubber baron on the Purus River, was "the model for the Caucho King in Da Cunha's essay Os Caucheiros".

[5] In 1909 Da Cunha was admitted as chairman and professor of Logic at the Colégio Pedro II, a public secondary school in Rio.