How did a few thousand Spanish Conquistadors subdue and conquer millions of Aztecs, Incas, and Mayans. Most scholars believe it's a combination of superior Spanish military technology, spreading of deadly infectious diseases, and internal tribal conflict that led to the demise of once powerful empires. In this talk to his Chinese high school students, Jiang Xueqin argues that it was the religious practices and beliefs of the native peoples of Central and South America that made them vulnerable to invasion and conquest. The natives had a strict religious hierarchy that established priest-kings as divine beings. When the Spanish executed their priest-kings, they broke the ultimate taboo. This left many Aztecs and Incas helpless and hopeless. Reference: The Mayans' Popol Vuh ("Book of the Community") can be read for free here: https://www.mesoweb.com/publications/Christenson/PopolVuh.pdf