HOW THEY DISAPPEARED...

One of the world’s greatest mysteries is what happened to the Mayans, Incas,  and Aztecs culture.  It was the most important civilization in the new world in A.D. 900.  Suddenly, however, the Mayas left their great cities and scattered throughout the countryside.  We still do not know why the great Mayan civilization ended.  Some people believe a natural disaster, disease, agriculture issues, a revolt, or an invasion caused people to leave the cities.  After the fall of the great Mayan cities, civil wars, epidemics, droughts, and hurricanes weakened the Mayan tribes.  This made it easy for the Spanish to conquer the land. 
The Spanish conquest of the Inca Empire started after years of preliminary exploration and military skirmishes.  It began as 168 Spanish soldiers and their native allies captured the Sapa Inca Atahualpa in the 1532. It took decades of fighting but ended in Spanish victory and colonization of the region.
Disease played a huge part in the fall of the Aztec empire.  The Spanish army introduced small pox to the Aztec people and many died.  Small pox spreads quickly. The Aztec did not know how to treat the disease.  The emperor died of small pox as well as many of the leaders in the army.  The Spanish army also used different tactics in war that also helped them defeat the Aztecs.

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