In 1519, a spanish explorer (Hernando Cortes) arrived at the east coast of mexico. He defeated the local tribes and set off for the Aztecs. When he arrived at the city, the spaniards captured the emperor, took him as a prisoner, and killed him.
The theory to their disappearance is, In 1521, the Spaniards demolished the aztec army. They captured the Aztecs treasure and sent it to spain. After two years they demolished