Prior to the discovery of the New World the Spanish had spent nearly 700 years taking the Iberian Peninsula back from the Muslims and had developed a culture in which those who had forfeited their souls through the rejection of Christ had no human value. Upon arriving in the New World the Spanish encountered a cultural horror that made Islam seem pale and weak. Human sacrifice, slavery, ritual and commercial cannibalism were widespread. At the center of this was the religion of the natives. Were it encountered today there would be a similar response by civilized people to stamp out the religions that fostered these practices.
Sound like Hitler now.