Tonatiuh was the Aztec sun god, believed to be the fifth sun, in whose era the Aztecs were currently living. According to Aztec mythology, Tonatiuh required human sacrifice in order to continue his daily journey across the sky. Thousands of people would be killed each year in his honor during the Aztec reign of the Valley of Mexico. This may be why not that long ago pozole was considered a funeral dish instead of being eaten on Mexico's biggest holiday of the year. These days, pozole takes on a new form, with a foundation in corn.
The dish's name is derived from the Nahuatl word pozolli which means foam. Cacahuazintle corn (a combination of the nahuatl words for cacao and corn), a large white dent heritage corn native to Mexico, creates that foam as it bursts into tiny florets while being boiled for the soup. This kind of corn is used to make sweets and tamales in certain parts of the country but its main use is for pozole.