In Aztec mythology, the underworld plays a crucial role, especially regarding themes of rebirth. The Aztec underworld, known as Mictlan, is where souls journey after death. The journey involves trials, determining whether a soul is destined for rebirth or eternal rest. This concept emphasizes life after death and the cyclical nature of existence, akin to agricultural cycles. The underworld's importance in rituals highlights the Aztec belief in continuity, affecting ceremonies that aimed to honor ancestors and assist souls in their transformative journeys towards rebirth.