1. Hernán Cortés, marqués del Valle de Oaxaca, was a Spanish conquistador who overthrew the Aztec empire and won Mexico for the crown of Spain. In 1518, Cortés was to command his own expedition to Mexico, but Velázquez canceled it.Cortés ignored the order and set sail for Mexico with more than 500 men and 11 ships that fall. In February 1519, the expedition reached the Mexican coast.