The Aztec Empire, also known as the Triple Alliance, was an alliance of three Nahua city-states: Tenochtitlan, Tetzcoco, and Tlacopan. It lasted from 1428 until 1521, when the Spanish *conquistadores* under Hernán Cortés defeated them.  *The maximal reach of the Aztec Empire. From [Wikipedia](https://commons.wikimedia.org/wiki/File:Aztec_Empire_1519_map-fr.svg).* ## Tenochtitlan Tenochtitlan was a city built by the Mexica people on a swampy island in the middle of Lake Texcoco, and was the largest and most powerful city in Mesoamerica, and the capital of the Aztec empire until the Spanish conquests.