Moctezuma II was the ninth emperor of the Aztec Empire, reigning from 1502 until his death in 1520. He is best known for his encounters with Hernán Cortés and the Spanish conquistadors, which ultimately led to the fall of Tenochtitlán and the collapse of the Aztec Empire. His leadership style and decisions during this period had profound effects on the indigenous peoples of Mesoamerica and the course of history in the Americas.