Aztlan

Where 1064 comes from

The year 1064 is a modern correlation rather than a date from a contemporary record. Domingo Chimalpahin's Memorial of Colhuacan, as translated and analysed by Rafael Tena, assigns the departure to the Indigenous year 1 Tecpatl and correlates that with 1064.

The Memorial says the Azteca Mexitin Teochichimeca left their dwelling at Aztlan and separated from its other inhabitants. Chimalpahin was writing in the early seventeenth century.

The codex gives a sign, not a year

The migration codex known as the Tira de la Peregrinación, or Codex Boturini, likewise begins with the Mexica leaving Aztlan in 1 Tecpatl — but the codex itself supplies no European-calendar equivalent.

Tena argued that a 52-year cycle omitted from the Tira reconciles its chronology with Chimalpahin's date: 188 visible year boxes plus one hypothesised missing cycle, representing 240 years from 1064 through 1303.

Read without that omission, the Tira can instead suggest 1116, while later correlations added to the Aubin and Azcatitlan codices give 1168.

What the exact day cannot support

No consulted scholarly source supports 4 January 1064 as the day of departure. The evidence supports, at most, a traditional year-level date.

The surviving migration sources are colonial-period records combining historical chronology, ancestral memory, political identity and mythic elements. Aztlan's location — and, in some interpretations, its historical existence — remains unresolved.

Tena tentatively connects the departure to the decline of the Toltec political order, but the precise historical trigger cannot be recovered.