Section Summary

During the last glacial period, modern humans crossed Beringia and entered the Americas for the first time, migrating across North, Central, and South America. They relied on hunting large game and may have contributed to the extinction of some animals. Later they became more settled in a number of regions, adapting their hunter-gatherer strategies to their environments and the available resources.

About nine thousand years ago, groups like those in the Andes region began experimenting with animal domestication. Later they began to cultivate edible plants like squash, bottle gourds, and later the potato. In Mesoamerica, the shift to maize-based agriculture began at some point between 5000 and 3000 BCE. By around 2500 BCE, the use of domesticated maize had become more common and enabled the settlement of agricultural villages that combined the strategies of hunting and gathering with maize cultivation. Over time, the advantages of maize agriculture became more obvious, and exclusively sedentary agricultural communities emerged. In the Eastern Woodlands, a different agricultural tradition emerged independently by 2000 BCE. In each area, plant domestication allowed Neolithic settlements to begin, from which larger cultures and civilizations later grew.

The Olmec civilization formed around 1200 BCE and developed sophisticated religious traditions, a calendar system, and a ritual ball game. The Olmec influenced Mesoamerican cultures that followed, including the Zapotecs of Oaxaca, the Teotihuacanos of the Valley of Mexico, and the Maya of southern Mexico and Guatemala. By 300 BCE, Teotihuacán was among the largest cities in the world and controlled a vast trading network. By that time, a handful of powerful Maya city-states like Tikal, Calakmul, and El Mirador had grown to large urban centers and were using their own sophisticated writing and calendar system.

In the Andes region of South America, Chavín culture began expanding around 900 BCE, spreading its distinctive artistic and religious traditions. In the wake of the Chavín collapse in 200 BCE, new states like the Moche, the Nazca, and the Tiwanaku emerged and thrived in the Andes.

In North America, the complex societies of the Adena tradition emerged in the Ohio River valley around 1000 BCE and built a number of earthen burial mounds. This tradition was followed by other mound-building cultures like the Hopewell tradition. Very different traditions developed in the Southwest, where maize agriculture was incorporated into a largely hunter-gatherer existence as early as the third millennium BCE. But in this dry environment, settled and entirely agricultural communities did not begin to emerge until around 200 CE.

In Mesoamerica in the fifteenth century, the Aztec Empire expanded to control central Mexico from its island city of Tenochtitlán. In addition to building large temples, ball courts, and palaces, the Aztec practiced human sacrifice as an important religious ritual. In the Andean region, the Inca Empire expanded to control a large swath of western South America from its capital at Cuzco, eleven thousand feet above sea level. The empire was created by trained warriors, employed a tribute system, and was held together by a vast network of roads through its largely mountainous terrain.

Intensive agriculture of maize in the Southwest and Eastern Woodlands led to enormous changes in both regions. By around 900, a number of settlements had grown in the Southwest, such as Pueblo Bonito in Chaco Canyon, the cliffside dwellings at Cliff Palace in Mesa Verde, and the larger Casas Grandes settlement in northern Mexico. In the Eastern Woodlands, the adoption of maize agriculture around 800 led to the rise of the Mississippian tradition and large agricultural communities across the Mississippi River valley. Most were small chiefdoms, but a few like Cahokia were exceptionally large, with populations in the thousands.