Garcilaso Inca de la Vega was born Gómez Suárez de Figueroa in Peru in 1539, just seven years after the first official encounter between Incas and Spaniards took place at Cajamarca. His father, Sebastián Garcilaso de la Vega, was a Spanish officer while his mother, Chimpu Ocllo, was an Inca palla, or princess of the royal family. Although they never married, the captain and the palla had at least two children and lived together for some ten years, until he took a Spanish bride. Garcilaso remained in his father's household until the latter's death in 1559, although he apparently also kept in close and frequent contact with his mother and her family.

As a mestizo, offspring of the union between an Amerindian and a Spaniard, both of whom were prominent residents of Cuzco, Garcilaso grew up in the privileged position of being able to learn the ways of two vastly different cultures and to witness the process of conquest from the perspectives of both the conquerors and the conquered. His earliest education seems to have been in Quechua, the language he considered his native tongue. Through his mother and the elders of her family, Garcilaso was introduced to the history and customs of the Incas. From comments he interspersed throughout his works we know that gatherings of the Incan side of the family were frequent and usually had a didactic effect on the young Garcilaso, who loved to hear stories of the empire's former grandeur and to satiate his curiosity with probing questions on life in Tahuantinsuyu, as the Inca empire was called in Quechua, before the arrival of the Europeans. Very little is known of his formal education.