The Aztecs were a Pre-Columbian Mesoamerican people of central Mexico in the 14th, 15th and 16th centuries. They called themselves Mexicas (Classical Nahuatl:. The capital of the Aztec empire was Tenochtitlan, built on raised islets in Lake Texcoco. The capital of Mexico, Mexico City, is built on the ruins of Tenochtitlan. The Aztec civilization had a vibrant culture which included mandatory education and a rich and complex mythology. For Europeans, the most striking element of the Aztec culture was the practice of human sacrifice which was practiced throughout Mesoamerica prior to the Spanish conquest. In what is probably the most widely known episode in the Spanish colonization of the Americas, Hernan Cortes conquered the Aztecs in 1521 thus immortalizing himself and the Aztec Huey Tlatoani , Moctezuma II (Montezuma II). The Aztecs spoke Classical Nahuatl as did some of the other peoples under the domination of the Aztec Empire. Although some contemporary Nahuatl speakers identify themselves as Aztecs, the word is normally only used as a historical term referring to the empire of the Mexicas, as distinguished from the Mexicas alone. Source Wikipedia