The Spanish Pioneers by Charles Fletcher Lummis

There is no reason whatever to doubt that Pizarro accepted this proposition in perfect good faith. The whole nature of the man, his religion, the laws of Spain, and the circumstantial evidence of his habitual conduct lead us to believe that he intended to set Atahualpa free when the ransom should have been paid. But later circumstances, in which he had neither blame nor control, simply forced him to a different course.

Atahualpa's messengers dispersed themselves through Peru to gather the gold and silver for the ransom. Meanwhile, Huascar, -- who, you will remember, was a prisoner in the hands of Atahualpa's men, -- having heard of the arrangement, sent word to the Spaniards setting forth his own claims. Pizarro ordered that he should be brought to Caxamarca to tell his story. The only way to learn which of the rival war-captains was right in his claims was to bring them together and weigh their respective pretensions. But this by no mean suited Atahualpa. Before Huascar could be brought to Caxamarca he was assassinated by his Indian keepers, the henchmen of Atahualpa, -- and, it is commonly agreed, by Atahualpa's orders.