At his coronation, Manco swore an oath committing the Inca monarchy to be a client state of Spain. This supposedly meant that Manco would rule independently while acknowledging the Spanish crown, for "The Inca should serve no one." Manco understood his position as that of an ally of the Spanish, but the whole charade was soon exposed. Soon after Manco's coronation, the Spanish systematically stripped the assets of the royal clans.

Manco decided to lead a revolt against the Spaniards. He called together his men in a secret meeting late one night in Cuzco. After listing other crimes, Manco spoke of the killing of Atahuallpa "without cause" and the murder of other generals and leaders, "burned alive in the fire so their souls would not go on to enjoy heaven." Manco concluded with these words: "I believe it would not be just or honest for us to accept this. Rather we should attempt with every determination either to die or to kill these cruel enemies." Passed down orally, but recorded from an eyewitness not long afterwards, Cieza's text agrees in general with the version recounted by Manco's son, Titsu Cusi, to a Spanish notary some 35 years later: "They have given me a thousand insults, they have imprisoned me, and chained me like a dog by the feet and by the neck, and worst of all they have done this after giving me their word that ... we had become allies."