Montezuma II was the ninth ruler of the Aztec Empire, reigning from 1502 to 1520. He is best known for his encounter with Spanish conquistador Hernán Cortés, which marked a significant moment in Mesoamerican history as it ultimately led to the fall of the Aztec Empire. Montezuma's leadership was characterized by a blend of military expansion, religious devotion, and political intrigue, reflecting the complex society of the Aztecs.