Even though conquistadors such as Cortés and Pizarro rode in on horses and shot with guns, bullets ultimately did not kill most of the Aztecs, Incas and other Native Americans. In addition to the supplies that the explorers carried with them on their ships, secret passengers also sailed the choppy seas of the Atlantic: germs. The Native Americans had never been exposed to germs from smallpox, measles and influenza, so their bodies had not learned to fight them off. Disease killed thousands of Native Americans in only a few years. To understand how powerful of a weapon these diseases were, look at these population numbers: When Columbus arrived in Haiti in 1492, approximately 100,000 people lived there. By 1570 there were only 300 people left! Before the conquistadors arrived, 25 million people lived in Mexico. Within a hundred years, there were only 3 million people left. Most of the Aztecs, Incas and other Native Americans were killed by the A guns and bullets of Cortés and Pizarro. B ships that brought the explorers to the New World. C conquistadors and their armies. D diseases that the explorers carried over on their ships.
