The Aztecs called themselves the Mexica. They formed part of a larger ethnic group known as the Nahua, who spoke Nahuatl. Unfamiliar with this language? You might know a few words: chocolate, chipotle, coyote, tomato, and avocado derive from Nahuatl words. Even the name Mexico, adopted after Mexicans gained independence from Spain in 1821, comes from Mexica.