How was the Inca Empire destroyed?

The Inca Empire was destroyed by the Spanish adventurer, Francisco Pizarro. It was a prosperous and well-governed empire. When Pizarro arrived, a fight for power was going on between Huascar and his half-brother, Atahualp Pizarro killed the latter while the former had already been killed. Leaderless, the Incas succumbed to the Spaniards.