The actual events that brought about Huáscar"s succession are unclear. Conflicting factions and the fact that the Spanish chroniclers" accounts stemmed from the winners of the ensuing civil war led to conflicting versions of what actually happened. Thus although Huayna Capac named the infant Ninan Cuyochi as his first heir, sources differ as to whether the boy died first, was unacceptable because of an unfavorable divination, or even if Huayna simply forgot that he had named him when asked to confirm the nomination.
In any event a second choice was requested and again sources vary.
He may have named Huáscar"s half-brother Atahualpa who then refused, or named Huáscar himself, or perhaps even the nobles put forward Huáscar. Whatever the truth, the result of Huáscar"s accession and the dispute over it before and after led to civil war between Huáscar (made Emperor by a faction based in Cuzco) and Atahualpa (backed by leaders who were based in the north with Huayna).
The Spanish chronicler Juan de Betanzos who provided with information pertaining to the Huáscar-Atahualpa civil war outlines Huáscar"s tyranny. This is however a very biased account, as Betanzos"s wife, on whose testimony much of his chronicle is based was previously married to Atahualpa.
Betanzos outlines how Huáscar would seize his lords" wives if they took his fancy.
More importantly, he seized both the Lands of the Previous Incas and the Lands of the Sun. In Inca society, the lands of previous dead Incas remained part of their household to support their divine-like cult. Similarly lands were reserved for the worship of the Sun.
In this way, Huáscar"s seizure represented his disrespect and insensitivity for Inca religion.
Huáscar then declared war on Atahualpa. The battles reported by Betanzos talk of Quizquiz (Atahualpa"s commander) leading armies of 60,000 men against armies of 60,000 men supporting Huáscar.
Betanzos"s account also enlightens us on the bloody nature of Inca wars. Atahualpa"s punishment of the Canares saw him rip the hearts from their chiefs and force their followers to eat them.
Huascar was defeated in the battle of Chimborazo and the Battle of Quipaipan.
Huascar was made prisoner, and Atahuallpa"s chiefs Quizquiz and Chalicuchima occupied Cuzco. The war had Atahualpa in the clear ascendancy on Pizarro"s arrival. However it was partly due to the ongoing civil war that Pizarro was able to triumph.
Firstly, the Inca armies were depleted from the civil war.
Secondly, disunity can be demonstrated by Huáscar"s celebrations and in the celebrations of the province of Cuzco (loyalists to Huáscar) at Atahualpa"s capture. Furthermore, Atahualpa had Huáscar killed so that he was not in a position to offer Pizarro a larger ransom of gold than Atahualpa was offering for his own release.