After Christopher Columbus tried to reach Asia in 1492 by sailing west of Africa, the Old World’s view of the planet changed. While Columbus wasn’t the first to discover the Americas, he was the first to establish settlements. The conquistadors who followed would forever change the lives of the indigenous people in the New World.

Communicable Diseases

Within 20 years of Columbus’ discovery of Hispaniola, the native population fell from one million to 30,000 thanks in part to diseases, according to the Library of Congress. The Spanish conquistadors saw their diseases as advantageous weapons since the indigenous populations did not have natural defenses against the new germs. For example, the University of North Carolina at Chapel Hill states that Hernan Cortes had a soldier with small pox who accidentally started an epidemic that killed one-third of the Aztec empire. Epidemics of measles, smallpox and other diseases had an important role in the conquering of the Americas, as the infirmaries wiped out up to 90 percent of some native populations, according to the University of Sydney.

Forced Labor and Slavery

When conquistadors found gold or another type of good they wanted to send back to Spain, they often forced the indigenous people of an area to harvest the commodity. With native populations on the decline because of mistreatment and diseases, the Spaniards imported African slaves to Hispaniola and other areas of the New World, according to the Library of Congress. When gold mining decreased, the conquistadors forced the slaves to grow and tend to sugar-cane fields in the Antilles, Mexico and Brazil.

Crops and Livestock

Just as the conquistadors took goods from the New World, they also introduced new commodities. The Gilder Lehrman Institute of American History explains that the Europeans did this to create an environment that resembled their Old World homes. Crops the conquistadors brought include sugarcane, rice and wheat. When Cortes arrived in Mexico in 1519, he had 16 horses. These horses were the first to step foot on the American continents, according to the University of North Carolina. Other animals the Spaniards introduced included pigs, goats, sheep, chickens, cats, cattle, donkeys, bees and new dog species.

New Ideas and Technologies

As the conquistadors conquered and established settlements, they introduced the indigenous people to new technologies and farming methods. One of the concepts introduced was the Roman alphabet; the native populations didn’t have a written language, according to Gettysburg College. The people of the land learned new farming techniques using tools such as plows. The conquistadors built homes, farms, chapels and other buildings using building patterns and designs similar to those in Europe. The soldiers also brought new weapons that helped the indigenous people fish and hunt with greater ease.