In the early part of the 15th century, the smallpox epidemic had reached Peru (from Central America) and killed more than 200,000 people. The Sapa Inca (Inca chief) consulted his people and performed religious rituals. But nothing worked. Thousands of Incas caught smallpox and died. Eventually the Sapa Inca Huayna Capac caught smallpox as well, and died without naming a clear heir: some said it was his 25-year-old son Atahuallpa and others said it was 21-year-old Huascar — Atahuallpa's younger brother by a different queen. The empire plunged into a bloody civil war.
Francisco Pizarro’s 3rd visit to the new world could not have been better timed. When he and his companions (168 in number) entered in to the plaza at Cazamarca where the Inca prince Atahualpa was camped with his 80,000 man army, the encounter was not a complete surprise to either people. Atahuallpa knew about the progress of Pizarro, but the war with his brother Huascar occupied all his attention. To Atahuallpa’s everlasting regret, he judged Huascar to be the greater threat. The Spaniards, after all, were only 160 men.
Pizarro sent one of his priests, Friar Vicente Valverde, to speak to Atahuallpa. Friar Vicente explained that the Spanish ruler was a friend of God and called upon the Inca to renounce their gods. Atahuallpa asked Friar Vicente what authority he had for his belief, and the friar told him it was all written in the book he was holding.
The Inca then said: "Give me the book so that it can speak to me."
Atahuallpa held the book next to his ear trying to listen to its pages.
At last he asked: "Why doesn't the book say anything to me?"
And he threw it on to the ground with a haughty and disdainful gesture. Father Vicente shouted that the Indians were against the Christian faith and gave the order to attack. The Spanish emerged with their guns from the porticoes around the square and fired in to the massed crowds of unarmed people.
Why did Atahuallpa walk into the trap? [Text excerpt: "Guns, Germs, and Steel," by Jared Diamond]
In hindsight, we find it astonishing that Atahuallpa marched into Pizarro's obvious trap at Cajamarca. The Spaniards who captured him were equally surprised at their success. The consequences of literacy are prominent in the ultimate explanation.
The immediate explanation is that Atahuallpa had very little information about the Spaniards, their military power, and their intent. He derived that scant information by word of mouth, mainly from an envoy who had visited Pizarro's force for two days while it was en route inland from the coast. That envoy saw the Spaniards at their most disorganized, told Atahuallpa that they were not fighting men, and that he could tie them all up if given 200 Indians. Understandably, it never occurred to Atahuallpa that the Spaniards were formidable and would attack him without provocation.
In the New World the ability to write was confined to small elites among some peoples of modern Mexico and neighboring areas far to the north of the Inca Empire. Although the Spanish conquest of Panama, a mere 600 miles from the Incas' northern boundary, began already in 1510, no knowledge even of the Spaniards existence appears to have reached the Incas until Pizarro's first landing on the Peruvian coast in 1527. Atahuallpa remained almost entirely ignorant about Spain's conquests of Central America's most powerful and populous Indian societies.
Pizarro too arrived at Cajamarca with no information about the Incas other than what he had learned by interrogating the Inca subjects he encountered in 1527 and 1531. However, while Pizarro himself happened to be illiterate, he belonged to a literate tradition. From books, the Spaniards knew of many contemporary civilizations remote from Europe, and about several thousand years of European history. Pizarro explicitly modeled his ambush of Atahuallpa on the successful strategy of Cortes.
Atahuallpa was arrested and put in his cell. It was then that Atahuallpa — now understanding that the Spanish wanted gold — came up with his plan to ransom himself for it. For the Incas, the Spanish desire for gold was both curious and fascinating. For them, gold had an aesthetic rather than a monetary value. They used it for decorating their shrines, for the images of their gods, but not for bartering. Atahuallpa believed that if he paid up, they would go away. It never seems to have occurred to him that these few — fewer than 200 — might be the precursors of thousands, who would come to settle permanently in his land, and that one payment of gold would not be enough.
Once the ransom was paid, Atahuallpa was executed and Manco Inca established as a puppet Inca ruler.