At the time of the Spanish Conquest, the indigenous population of what we now call Mexico, was about 20,000,000. By 1600, after the introduction of European diseases, only about a million remained. The four big killers were small pox, measles, mumps, and pneumonia. In 1545, over 800.000 people died in one small pox outbreak alone. Bartolome de Las Casas, the first clergyman ordained in the New World tells us that the conquistadors destroyed between 15,000,000 and 20,000,000 Native Americans in the Western Hemisphere. Most were enslaved, branded, and sold on the world market for fifty gold pesos.