Civilizations in the Americas emerged separately from other major civilizations in the world. The indigenous people of the Americas are believed to have been immigrants from Asia, who crossed over to America during the Ice Age, approximately 20,000 years ago. These new immigrants quickly spread throughout the Americas, in small and culturally distinct groups. The development of agriculture in the Americas five thousand years ago led to the flourish of new culturally advanced societies and innovations. Pre-Columbian American civilizations, such as the Mayas, Aztecs, Incas, and Olmecs were socially stratified and technologically advanced.
In this unit, we will see that civilizations developed in two main regions of the Americas: Mesoamerica and the Peruvian highlands. In fact, we will see that the entire area that stretched from central Mexico to Chile formed a continuous chain of developing civilizations.