This indicates that there was a very strong cult towards death among the ancient Mexicans, and also among the Mayans, the Tarascans and the Totonacs, who also had a great devotion to death.
Then, the Spanish arrived and it was thought that the cult to death would be forgotten, but that was not the case: Mictlantecuhtli and Mictecacihuatl (mainly the latter) remained hidden and many of their devotees continued following them.
In his study on the Holy Death, the archaeologist Carlos Navarrete suggests that the popular devotion could be due to the syncretism between a Christian deity related to death and Saint Pascual Baylon, a Catholic saint and the Animas Solas (Lonely Souls).
The Spanish Conquest was imposed by “blood and fire” on the indigenous people of Mexico, but there were also another conquest: the spiritual one, which was the total destruction of the divinities that made up the indigenous culture. However, despite all their efforts, some traces of the ancient religion still remained within Catholicism and the cult to the Holy Death is part of that distant past.
The conversion of the indigenous peoples was paramount for the Franciscan missionaries, and the resistance of the natives towards the new religious doctrines was a permanent condemnation for evangelisers. The malpractice of some indigenous people was denounced in a text written in c. 1600 which mainly described the idolatries in the small village of Tuxtla.
The only true God for Catholics was the one that was established in the Bible. Therefore, when they found another religious thought, they condemned it as if it was a satanic rite: but this was unfair since in Ancient Mexico the concept of hell was not known. The indigenous gods were venerated in pyramids, in hills and in caves, and during the first years of evangelisation the Catholic missionaries did not understand why people used to dance around bones (which had often belonged to high priests or leaders, and that was why they worshipped them). These were only some of the religious practices of the time, which were beyond the comprehension of the minds of conquerors and evangelisers.
To try to hide these practices, the faithful devotees of Mictlancihuatl most probably “dressed” the cult of this goddess with elements of Catholicism to avoid being punished. The mixture of both roots -Indigenous and European- and the addition of Creole elements gave rise to the cult of the Holy Death, as we know it today.