The Dawson Ledger
Event

Tepanec War and Formation of the Triple Alliance (c.1427-1428 CE, conventional)

Founding war of the Aztec Triple Alliance (Smith 2012; Hassig 1988).

Mesoamerican

Event Details

  • Date: c.1427 CE-1428 CE (conventional; not extracted from a source)
  • Type: war
  • Civilizations: mesoamerican

Description

Founding war of the Aztec Triple Alliance (Smith 2012; Hassig 1988).

Quantitative facts and their sourcing

  • Wikipedia (Itzcoatl): under Itzcoatl (reign 1427-1440) the Mexica of Tenochtitlan broke free from Tepanec domination and, with Tetzcoco and Tlacopan, founded the Triple Alliance. The war against Azcapotzalco (Tepanec capital) is conventionally dated 1427-1428; the exact dates are NOT given in the fetched infobox. No casualty or strength figures asserted.
  • Candidate formal sources listed in the Wikipedia infobox/lead for this topic (METADATA-VERIFIED ONLY via Crossref/Open Library; NOT read; relevance to the figures above unverified): Townsend Camila 2019, Fifth Sun.
  • PRIMARY-SOURCE (read 2026-10-12): Duran, Historia t. 1, cap. IX (pp. 69-78): Itzcoatl's election given as "mil y quatrocientos y veinte y quatro" (1424, Duran's date); Tlacaelel led the Mexica; Azcaputzalco was entered and sacked, "no dexando ... ni hombre ni muger ni nino a vida, saluo los que huyendo se auian acoxido a los montes"; the Tepanecs surrendered as "perpetuos tributarios" and ceded lands. No numbers. Sixteenth-century friar's history based on Nahua sources.

Confidence

low-medium (event real; dates conventional). Numbers marked "Wikipedia-compiled (stub)" come from a secondary aggregator and must be upgraded to page-level scholarly citations before any Official use.

Citations

  • duran-historia-t1-1867-ia [PRIMARY-READ] Diego Duran, J. F. Ramirez (ed.) (1867). Diego Duran, Historia de las Indias de Nueva Espana y islas de Tierra Firme, t. 1, ed. J. F. Ramirez (Mexico, 1867); archive.org scan, read. Imprenta de J. M. Andrade y F. Escalante (scan: Internet Archive). https://archive.org/details/historiadelasind01dur. Read 2026-10-12; location: cap. IX, pp. 69-78 (Itzcoatl and Azcaputzalco); cap. LV, pp. 434-435 (xuchi yaoyotl).
  • smith2012-aztecs [formal] Michael E. Smith (2012). The Aztecs (3rd ed.). Wiley-Blackwell. https://openlibrary.org/works/OL2939796W. Verified 2026-10-11 (Open Library record found; edition exists, page-level not checked).
  • hassig1988-aztec-warfare [formal] Ross Hassig (1988). Aztec Warfare: Imperial Expansion and Political Control. University of Oklahoma Press. https://openlibrary.org/works/OL4119738W. Verified 2026-10-11 (Open Library record found; edition exists, page-level not checked).
  • wp-itzcoatl [STUB (secondary aggregator)] Wikipedia contributors (2026). Itzcoatl (Wikipedia; secondary aggregator, stub-grade). Wikipedia. https://en.wikipedia.org/wiki/Itzcoatl. Verified 2026-10-11 (resolves).
  • m-townsend2019-fifth-sun [formal] Townsend Camila (2019). Fifth Sun. Oxford University Press. https://openlibrary.org/books/OL28264987M. Verified 2026-10-11 (Open Library record found; edition exists, page-level not checked).

Review status

SOFT draft. Not Official. Needs editor review of CAD tags (estimated) and page-level citation upgrade.

About this entry

A draft entry preserved from civilization.study. Evidence grade: low. 4 of 5 listed sources are fully documented; the rest are names only. Method and sources

Conflict card

This card is generated from Civitas's war record and carries the same evidence badge as every other conflict card.

How to read the evidence badges
Primary text read
Civitas read the ancient or primary text for at least one figure on this card. Other figures may still be Wikipedia-compiled and are labelled.
Generic placeholder: an advancing line for a war or campaign. Not an image of this event.
war · c.1427 CE-1428 CE (conventional; not extracted from a source)

Tepanec War and Formation of the Triple Alliance (c.1427-1428 CE, conventional)

Founding war of the Aztec Triple Alliance (Smith 2012; Hassig 1988).

Evidence: Primary text read Draft estimate

What the record says

  • Unverified (Wikipedia-compiled) Wikipedia (Itzcoatl): under Itzcoatl (reign 1427-1440) the Mexica of Tenochtitlan broke free from Tepanec domination and, with Tetzcoco and Tlacopan, founded the Triple Alliance. The war against Azcapotzalco (Tepanec capital) is conventionally dated 1427-1428; the exact dates are NOT given in the fetched infobox. No casualty or strength figures asserted.
  • Candidate sources Candidate formal sources listed in the Wikipedia infobox/lead for this topic (METADATA-VERIFIED ONLY via Crossref/Open Library; NOT read; relevance to the figures above unverified): Townsend Camila 2019, Fifth Sun.
  • Primary text PRIMARY-SOURCE (read 2026-10-12): Duran, Historia t. 1, cap. IX (pp. 69-78): Itzcoatl's election given as "mil y quatrocientos y veinte y quatro" (1424, Duran's date); Tlacaelel led the Mexica; Azcaputzalco was entered and sacked, "no dexando ... ni hombre ni muger ni nino a vida, saluo los que huyendo se auian acoxido a los montes"; the Tepanecs surrendered as "perpetuos tributarios" and ceded lands. No numbers. Sixteenth-century friar's history based on Nahua sources.

Confidence. low-medium (event real; dates conventional).

Where it sits

Sources and evidence

No page-level citation is claimed for any source. Figures marked unverified come from a Wikipedia aggregator and are not for Official use.

Link to this conflict

Art: Patterns of Civilization chronicle art, made with AI: illustrations, not historical evidence. Entries are drafts preserved from civilization.study. Method and sources.