Why was Montezuma II killed?

Montezuma II, the ninth emperor of the Aztec Empire, was killed primarily due to the conflict between the Aztecs and Spanish conquistadors led by Hernán Cortés. After initially being taken captive and used as a puppet ruler, he lost the trust of his people amid the Spanish siege of Tenochtitlan. His death occurred in 1520 during a violent clash, likely caused by a combination of Aztec resentment towards his collaboration with the Spaniards and the chaos of the Spanish retreat from the city. Ultimately, Montezuma's demise marked a significant turning point in the Spanish conquest of the Aztec Empire.