The Americas

A timeline shows important events of the era. In ca. 13,000 to ca. 7000 BCE, humans cross the land bridge between Asia and North America. In ca. 5000 BCE, corn is domesticated in Mesoamerica; an illustration of the corn plant is shown. In ca. 2000 BCE to ca. 900 CE, Mayan civilization flourishes in the Yucatán Peninsula; Mayan pottery is shown. In 622, Muhammad receives the vision for Islam; an illustration of Muhammad is shown. In ca. 1000, Leif Ericson arrives in present-day Canada; a painting depicting Ericson’s arrival is shown. In ca. 1100, Cahokia is at its peak near modern St. Louis. In 1325–1521, Aztec civilization flourishes in present-day Mexico; a map of Tenochtitlán is shown. In 1346, the Black Death decimates Europe; an illustration of Black Death victims is shown. In 1492, Columbus arrives in the Bahamas; a painting of Columbus’s arrival is shown. In 1400–1532, the Inca Empire thrives in South America.
(credit: modification of work by Architect of the Capitol)

Between nine and fifteen thousand years ago, some scholars believe that a land bridge existed between Asia and North America that we now call Beringia. The first inhabitants of what would be named the Americas migrated across this bridge in search of food. When the glaciers melted, water engulfed Beringia, and the Bering Strait was formed. Later settlers came by boat across the narrow strait. (The fact that Asians and American Indians share genetic markers on a Y chromosome lends credibility to this migration theory.) Continually moving southward, the settlers eventually populated both North and South America, creating unique cultures that ranged from the highly complex and urban Aztec civilization in what is now Mexico City to the woodland tribes of eastern North America. Recent research along the west coast of South America suggests that migrant populations may have traveled down this coast by water as well as by land.

Researchers believe that about ten thousand years ago, humans also began the domestication of plants and animals, adding agriculture as a means of sustenance to hunting and gathering techniques. With this agricultural revolution, and the more abundant and reliable food supplies it brought, populations grew and people were able to develop a more settled way of life, building permanent settlements. Nowhere in the Americas was this more obvious than in Mesoamerica (Figure).

A map shows the locations of the Olmec, Aztec, Maya, and Inca civilizations, in, respectively, present-day Mexico; present-day Mexico; present-day Mexico (on the Yucatán Peninsula),Belize, Honduras, and Guatemala; and present-day Ecuador, Peru, and Bolivia.
This map shows the extent of the major civilizations of the Western Hemisphere. In South America, early civilizations developed along the coast because the high Andes and the inhospitable Amazon Basin made the interior of the continent less favorable for settlement.