How did Spanish colonization affect people in the Americas and in Europe

Over the course of the next 350 years:

Spain ruled a vast empire based on the labor and exploitation of the native population.

Conquistadors descended on America with hopes of bringing Catholicism to new lands while extracting great riches.

Religion and self-interest combined to create a potent mixture that drew hundreds of thousands of Spaniards across the ocean with hopes of finding riches and winning souls for God.

But along with the Spaniards came diseases to which the New World natives had no immunities.

What followed was one of the greatest tragedies in human history as smallpox, influenza, and other communicable diseases ravaged the native populations, killing millions. Yes, a lot.