The celebration can be traced to many Mesoamerican native traditions, such as the festivals held during the Aztec month of Miccailhuitontli, ritually presided by the “Lady of the Dead” (Mictetecacihuatl) dedicated to children and the dead.
From the Aztec, Mayan and other indigenous traditions come the knowledge that souls continue to exist after death, resting placidly in Mictlan, the land of the dead, for the day each year when they could return home to visit their loved ones.
In the Aztec calendar, this ritual fell at the end of July and the beginning of August, but in the post conquest era it was moved by Spanish priests so that it coincided with the Christian holiday of All Hollows Eve (Día de Todos los Santos).
It consists of families welcoming their dead back into their homes, and visiting the graves of their close kin. The traditional observance calls for departed children to be remembered during the first day of the festivity (the Day of the Little Angels, “Día de los Angelitos”), and for the adults to be remembered on the second day.