Juan Valiente was born in West Africa around 1505 and purchased at a very young age by a Portuguese trader. He was later purchased by a Spaniard by the name of Alonso Valiente and eventually baptized. Juan convinced his owner to let him pursue a career as a conquistador for four years providing that he kept an account of the earnings and bring them back to his master. In order for his agreement to stand, he had to keep a notarized record of the agreement on his person at all times "in order to avoid being arrested as a slave in flight."
Juan participated in many expeditions including the Pedro de Alvarado expedition in Guatemala and the Juan de Valdivia expedition in Chile in which he was a captain and horseman. He subsequently earned an estate in Santiago and an encomienda in which he received tribute from Indians. He married Juana de Valdivia who is cited as possibly being a native servant of a former African slave of Governor Juan de Valdivia.
Alonso Valiente soon sought a return on his investment and sent out an updated version of the agreement he had with Juan but Juan did not initially receive it. He had, in fact, attempted to purchase his freedom by way of a royal officer in 1550 but the officer ran off with his money. Five years after the first attempt to contact Juan, Alonso Valiente attempted to contact him again, but was unsuccessful. Juan had been killed in the Battle of Tucapel. There have been reports that suggest that in an effort to retrieve his money, Alonso sued the widow Juana de Valdivia for the estate left by her husband (Restall 2003:53–54).