A Correlation of Gregorian and Tonalpohualli Dates on the Aztec Calendar Stone

This essay proposes that the central message conveyed in the Aztec Calendar Stone (ACS) was to commemorate and merge the mythistoric creation of last Mexica era, the “Fifth Sun,” with the ascension of Motecuhzoma II to the Mexica throne. This conflation of mythic time with an historic event can be understood by reading certain of the monument’s ideograms as representing specific days in the Mexica divining calendar (tonalpohualli). After a brief description of the ACS, I introduce a memorial that commemorated the 1503 C.E. inauguration of Motecuhzoma II and I examine selected ideograms for their significance in Mexica religion. I then correlated the Gregorian calendrical days designated by the ideograms with astronomical events recognized as important by the Mexica; this resulted in a sense of singularity to the year 1503 C.E. I then searched for a year whose dates corresponded to 1503 C.E. with a near-perfect match found in 1167 C.E., a year that marked the final throes of the Toltec civilization. The possible reason for the conflation of 1167 C.E. and 1503 C.E. is examined and I end the essay with the inclusion of data that suggests the presence of two 365-day calendars (xiuhpohualli) within the year studied.