Nahua Dates

Dates in Nahuatl-language documents follow a consistent formula, built from a small set of recurring words. Once you recognize these building blocks, most date lines become easy to understand, even when spelling varies from scribe to scribe. This page focuses on that vocabulary and the different ways these elements were combined and written out, as well as the naming patterns used for Catholic feast days. For a breakdown of how numbers themselves work in Nahuatl (including ordinals and roman numerals), see the Numbers page.

The Nahua adopted the Spanish months and days of the week, borrowing the words directly rather than inventing native equivalents. Nahuatl already had its own word for "month" (metztli, literally "moon"). Rather than replacing it, scribes simply paired it with the borrowed Spanish month name — "metztli de mayo," (the month of May). The seven-day week worked the same way, since it had no pre-Conquest equivalent. The result combines native grammar and vocabulary with Spanish (and sometimes Latin) loanwords for days and months of the Spanish calendar. Below are the days of the week and months of the year, along with a non-exhaustive list of spelling variations found in the writings of Indigenous scribes:

Feast days are special days that celebrate and honor Jesus, Mary, or other saints. Most saints have a fixed feast day once a year (also known as the sanctorale). Most saints have a fixed date every year (for example, the feast of Saint Andrew is always November 30), making these entries a reliable, unchanging way to mark a date. In the image below, it says "yni ilhuitzin Sancta Andrés," "the feast day of Saint Andrew."

Some major feasts are Easter, Pentecost, Corpus Christi, and Ash Wednesday. These feast days don’t occur on the same day each year but shift each year in relation to when Easter is (known as the temporale). Knowing that year's Easter date is the key to pinning down the other movable feast days. See the Genealogical Feast Day Calendars  on the FamilySearch wiki to learn more.

Feast days are rarely mentioned outright in maya parish baptism, marriage, and burial records. The one example here is more of a bonus find than something to expect regularly. However, the practice of naming a child after the saint whose feast day fell on or near their birth or baptism carried over into colonial New Spain. For example, a child would likely be named Andrés if born or baptized on November 30, the feast of Saint Andrew. Most of these names came from the sanctorale instead of the temporale. While naming children after saints is very common, children were just as often named after parents, godparents, or other family traditions.

Sources for Images in Order of Appearance:
"Registros parroquiales de San Gabriel Arcángel, 1605-1955," burial entry for Francisca Monica, 4 May 1623, San Gabriel Arcángel, Miguel Hidalgo, Mexico City, Mexico, digital image, FamilySearch (https://www.familysearch.org/ark:/61903/3:1:939D-8PXP-Y?view=explore&groupId=TH-1-11153-11413-26&lang=en :  accessed 16 July 2026), IGN 4565710, image 19 of 581.
"Registros parroquiales, 1620-1975," burial entry for Heronimo, 26 December 1640, San Juan Bautista, San Juan Bautista Tlachichilco, Oaxaca, Mexico, digital image, FamilySearch (https://www.familysearch.org/ark:/61903/3:1:939F-SJVM-3?view=explore&keywords=Axca&lang=en&groupId=M9Z5-PRQ&cat=true :  accessed 16 July 2026), IGN 4611601, image 170 of 618.
"Registros parroquiales, 1582-1957,”  marriage entry for Pedro and Mariana, 11 December 1644, Nuestra Señora de la Natividad, Atlixco, Puebla, Mexico, digital image, FamilySearch (https://www.familysearch.org/ark:/61903/3:1:939J-Q7QL-J?cat=koha%3A279581&view=explore&lang=en&groupId=M97K-GBN :  accessed 16 July 2026), IGN 4651964, image 17 of 513.
"Registros parroquiales, 1619-1961,”  marriage entry for Juan Contreras and Maria, 30 November 1619, El Sagrario, Toluca, Mexico, digital image, FamilySearch (https://www.familysearch.org/ark:/61903/3:1:939F-V41Z-2?view=explore&groupId=M945-T76&lang=en&cat=true :  accessed 17 July 2026), IGN 4010652, image 10 of 669.