This study does not speculate about the nebulous history of ancient American civilizations but it sustains bold analysis where enough historical material exists. When evidence is lacking the most prevalent academic interpretations are delineated with a critical overview. Customs and rituals are examined in socioeconomic terms: for example, the Aztecs' human sacrifices of thousands are viewed in the context of a society which raised its productivity through an intricate irrigation system yet could not ensure constant growth and hence solved the problem of redundant population by exterminating surplus people with religious sanctions. Stratifications and social laws along with rituals and traditions of the Aztecs and Incas are compared. Katz's analysis of Inca ""primitive communism"" contains interesting references to the prejudices of past historians who tended either to extol it as an enlightened utopia or condemn its encroachments on ""individual liberties."" The book covers the predecessors of the Incas and Aztecs (surveying alternate theories, Katz adheres to the view that the first American settlers came from Siberia by way of Alaska) and ends with the devastating effects of the Spanish conquest. Altogether an excellent overview for students and amateur historians.