In ancient Aztec religion, what was the underworld called?

In ancient Aztec religion, Mictlan was the underworld. It was associated with the dead who did not go to destinations reserved for particular kinds of deaths, such as warriors, sacrificed people, or those connected with the rain deity Tlaloc.

Aztec accounts describe the journey to Mictlan as difficult and involving multiple stages or challenges. A dead person was traditionally accompanied by a dog, often identified with the hairless xoloitzcuintli, which could help the soul cross a dangerous river.

Mictlan was ruled by Mictlantecuhtli and Mictecacihuatl, commonly identified as its lord and lady. It is often confused with Tlalocan, a separate paradise associated with Tlaloc, or with Aztlan, the ancestral homeland in Mexica origin traditions. Surviving descriptions come from colonial-era sources that recorded Indigenous beliefs after Spanish contact.