About 35,000 years ago, the Ice Age solidified much of the world oceans into mammoth glaciers this caused the ocean level to decrease. As the sea level dropped, it bared a land bridge adjoining Eurasia and Alaska, what are present-day Siberia and Alaska. The Native American ancestors crossed the land bridge into North America, most probably following migrating animals. As the Ice Age ended the water level rose again causing the land bridge to be submerged once again in the ocean, thus leaving the ancestors of the Native Americans abandoned on an isolated continent. After crossing the land bridge the Native Americans spread and formed a variety of cultures and a few civilizations.
The cultivation of maize played an essential and vital role in the building of the earliest American civilizations. Two of the most glorious and sophisticated civilizations the Incas in Peru, and the Aztecs in Mexico were based primarily on the cultivation of maize.
Discovered around 5,000 B.C, hunter-gatherers in Mexico embraced this crop and made it the foundation of the complex, large scaled centralized Aztec and Incas nation-states that eventually emerged. This was mainly because the cultivation of maize helped feed the large populations in those ancient cities. The cultivation of maize spread across the Americas from the Mexican heartland. As it was planted, maize started to alter nomadic hunters into settled agricultural villagers and builders of complex civilizations, but this process went forward gradually and immethodically.
The Incas were a single people with a single language living in a highland center, Cuzco. Unlike the military empires in Central America, the Incas ruled by proxy. After conquering a people, they would incorporate local rulers into their imperial system, generously reward anyone who fought for them, and treated well all those conquered people whom cooperated. In reality, the...