The Mexica, or Aztecs, were a Mesoamerican civilization that inhabited the Valley of Mexico from around 1325 to 1521 AD. They spoke Nahuatl and practiced polytheistic religion, sacrificing prisoners of war to appease the gods. The Aztec Empire dominated much of Mesoamerica through warfare and tribute until it was conquered by the Spanish under Hernán Cortés in 1521 with the help of La Malinche, who served as a translator.