11. The Americas, 2500 B.C.E.–1500 C.E.

When peoples of the Americas first came into sustained contact with peoples from Europe, Africa, and Asia at the turn of the sixteenth century, their encounters were uneven. Thousands of years of isolation from other world societies made peoples of the Americas vulnerable to diseases found elsewhere in the world. When indigenous peoples were first exposed to these diseases through contact with Europeans, the devastating effects of epidemics facilitated European domination and colonization. But this exchange also brought into global circulation the results of thousands of years of work by peoples of the Americas in plant domestication that changed diets worldwide, making corn, potatoes, and peppers into the daily staples of many societies.

The ancient domestication of these crops intensified agriculture across the Americas that sustained increasingly complex societies. At times these societies grew into vast empires built on trade, conquest, and tribute. Social stratification and specialization produced lands not just of kings but of priests, merchants, artisans, scientists, and engineers who achieved extraordinary feats.

In Mesoamerica — the region stretching from present-day Nicaragua to California — the dense urban centers of Maya, Teotihuacan, Toltec, and Mexica city-states and empires featured great monuments, temples, and complex urban planning. Roadways and canals extended trade networks that reached from South America to the Great Lakes region of North America. Sophisticated calendars guided systems of religious, scientific, medical, and agricultural knowledge.

These achievements were rivaled only in the Andes, the mountain range that extends from southernmost present-day Chile north to Colombia and Venezuela. Andean peoples adapted to the mountain range’s stark vertical stratification of climate and ecosystems to produce agricultural abundance similar to that of Mesoamerica. The technological, agricultural, and engineering innovations of ancient Andean civilizations allowed people to make their difficult mountain terrain a home rather than a boundary.