Lope de Aguirre (Spanish pronunciation: ['lope ðe a'?ire]; 8 November 1510 – 27 October 1561) was a Basque Spanish conquistador who was active in South America.
Nicknamed El Loco ('the Madman'), he styled himself "Wrath of God, Prince of Freedom, King of Tierra Firme".
Aguirre is best known for his final expedition down the Amazon river in search of the mythical golden Kingdom El Dorado.
In 1561 Aguirre sent a letter which defied the Spanish monarch Philip II by declaring an independent state of Peru.
Aguirre's expedition ended with his death, and in the years since then he has been treated by historians as a symbol of cruelty and treachery in the early history of colonial Spanish America, and has become an antihero in literature, cinema and other arts.