The precise origins of the worship of Santa Muerte are a matter of debate, but it is most likely a syncretism between Mesoamerican and Spanish Catholic beliefs.Mesoamerica had always maintained a certain reverence towards death, which manifested itself among the religious practices of ancient Mexico, including in the Aztec religion. Death was personified in Aztec and other cultures in the form of humans with half their flesh missing, symbolizing the duality of life and death. From their ancestors the Aztecs inherited the gods Mictlantecuhtliand Mictecacihuatl, the lord and lady of Mictlan, the realm of those dead who died of natural causes. In order for the deceased to be accepted into Mictlan, offerings to the lord and lady of death were necessary. In European Christian tradition, many paintings employed skeletons to symbolize human mortality.