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Early life and parentage

Pachacuti's given name was Cusi Yupanqui, and he originated from the female lineage of Iñaca Panaka, in the moiety of Hanan Cusco ("high Cusco"), in complementary opposition to the moiety of Hurin Cusco ("low Cusco"). According to the accounts of the Spanish chroniclers, he was the son of the eighth ruler of Cusco, Inca Viracocha, whose lineage (panaka), however, was Sucsu Panaka. Analyzing the colonial writings, the historian and anthropologist María Rostworowski concluded that, based on Andean traditions of succession, which allowed for the "most capable" to take power, Pachacuti was not the son of Inca Viracocha, rendering him illegitimate in the eyes of the Spaniards, who believed in European concepts of primogeniture.

Cusi Yupanqui was born in Cusco, at the palace of Cusicancha, bordering the Inticancha temple. His tutor, Micuymana, taught him history, laws and language, as well as the handling of quipus. From a young age, he was admired by Inca nobles because he had the courage, intelligence and maturity his brother, Inca Urco, the appointed co-ruler and heir to the throne, lacked. Similarly, he showed aptitudes for government and conquest that his brother likewise lacked. The generals of Viracocha started fomenting conspiracies to overthrow and replace Inca Urco.