Pizarro was born born at Trujillo in Estremadura, Spain, about 1471 (or 1475). He was an illegitimate son of Gonzalo Pizarro, who as colonel of infantry afterwards served in Italy under Gonsalvo de Cordova, and in Navarre, with some distinction.
Of Pizarros early years hardly anything is known; but he appears to have been poorly cared for, and his education was neglected. Shortly after the news of the discovery of the New World had reached Spain he was in Seville, he sailed to the New World in 1509 and took part in various Spanish missions of exploration and conquest. He is heard of in 1510 as having taken part in an expedition from Hispaniola to Urab under Alonzo de Ojeda, by whom he was entrusted with the charge of the unfortunate settlement at San Sebastian.
He accompanied Vasco Nuņez de Balboa (whom he afterwards helped to bring to the block) in the discovery of the Pacific; and under Pedrarias d'Avila he received a repartimento, and became a cattle-farmer at Panama. Here in 1522 he entered into a partnership with a priest named Hernando de Luque, and a soldier named Diego de Almagro, for purposes of exploration and conquest towards the south. Pizarro, Almagro and Luque afterwards renewed their compact in a more solemn and explicit manner, agreeing to conquer and divide equally among themselves the opulent empire they hoped to reach. Explorations were then undertaken down the west coast of South America, in which Pizarro, though left for months with but thirteen followers on a small island without ship or stores, persisted till he had coasted as far as about 9 S. and obtained distinct accounts of the Peruvian Empire.
The governor of Panama showing little disposition to encourage the adventurers, Pizarro resolved to apply to the sovereign in person for help, and with this object sailed from Panama for Spain in the spring of 1528, reaching Seville in early summer. Charles V was won over, and on the 26th of July 529 was executed at Toledo the famous capitulacion, by which Pizarro was upon certain conditions made governor and captain-general of the province of New Castile for the distance of 200 leagues along the newly discovered coast, and invested with all the authority and prerogatives of a viceroy, his associates being left in wholly secondary positions. One of the conditions of the grant was that within six months Pizarro should raise a sufficiently equipped force of two hundred and fifty men, of whom one hundred might be drawn from the colonies; as he could not make up his due complement he sailed clandestinely from San Lucar in January 1530.
He was afterwards joined by his brother Hernando with the remaining vessels, and when the expedition left Panama in January of the following year it numbered three ships, one hundred and eighty men, and twenty-seven horses.
After the final effort of the Incas to recover Cuzco had been defeated by Almagro, a dispute occurred between him and Pizarro respecting the limits of their jurisdiction. This led to battle; Almagro was defeated at the City of Ute (1538) and executed; but his supporters conspired, and assassinated Pizarro on the 26th of June 1541.