When Cortés landed, according to the Berkeley researchers Cook and Borah, 25.2 million people lived in central Mexico, an area of about 200,000 square miles. After Cortés, the population of the entire region collapsed. By 1620–25, it was 730,000, “approximately 3 percent of its size at the time that he first landed.” Cook and Borah calculated that the area did not recover its fifteenth-century population until the late 1960s.
