Who was the king of the Aztecs when hernam Cortes invaded?

The king of the Aztecs when Hernán Cortés invaded in 1519 was Moctezuma II. He ruled from 1502 until his death in 1520 and was the ninth ruler of the Aztec Empire. Moctezuma initially welcomed Cortés and his men, believing them to be representatives of the god Quetzalcoatl, but later faced significant challenges as the Spanish sought to conquer the empire. His reign ended tragically amid the Spanish conquest and subsequent violence.