The Fall of the Aztec Empire

In 1519 Hernán Cortés landed on the Mexican coast with about 500 Spaniards and marched inland toward Tenochtitlán, the Aztec capital. He won because the Aztec empire ruled by extracting tribute and captives from the peoples around it, and those peoples — above all the Tlaxcalans — joined him in tens of thousands; Indigenous allies did most of the fighting. The emperor Moctezuma received Cortés into the city and was taken hostage; when the Spanish were driven out in 1520 with heavy losses, smallpox arrived in their wake and swept the city, killing a vast share of its defenders and its new emperor. Cortés returned in 1521 with his allies and besieged a capital already devastated by disease. It is the pattern of conquest as it usually happens: not a superior people overwhelming a lesser one, but disease and existing local divisions doing what swords alone could not.