Pedro de Valdivia is believed to have been born in
Villanueva de la Serena
 (some say
Spain around 1500 (some sources put his date of birth as early as 1497 or as late as 1505) to an impoverished
hidalgo family. In 1520 he joined the Spanish army of
Charles I and fought in
Flanders in 1521 and Italy between 1522 and 1525, participating in the
battle of Pavia as part of the troops of the
Marquis of Pescara. He reached America in 1535, spent an uneventful year in
Venezuela, and then moved on to
Peru in 1537.
There he took part on the side of
Hernando Pizarro in his struggle against
Diego de Almagro and fought in the
battle of Las Salinas in 1538, which saw Almagro defeated and captured.
:264 Afterwards he accompanied Hernando and Gonzalo Pizarro to conquer both the province of Collao and las Charcas in High Peru (currently
Bolivia). As compensation for his help in conquering these lands, he was awarded a silver mine and became a wealthy man.
Valdivia had married
Marina Ortíz de Gaete in Spain,
 but in Peru he became attached to the widow
Inés de Suárez, who was to accompany him to Chile as his mistress.