Atahualpa was the "Sapa Inca" (unique Inca)* who confronted the Spaniard Francisco Pizarro on November 16, 1532. His army of approximately 6000 soldiers entered Cajamarca and tried to fight against Pizarro's small army of 168 men. After a couple of hours, most of the Inca army lay dead.
Taken from: Kenneth Adrien, Andean Worlds: Indigenous History, Culture and Consciousness.