Ācamāpīchtli was the first tlatoani (ruler) of the Tenochca, a group of Mexica that would later become known as the Aztecs, and as such he is generally considered to be the first ruler of the Aztecs1. At this time the Aztec 'empire' was still part of the Azcapotzalco, and Acamapichtli remained a vassal of the Azcapotzalco leader Tezozomoc.

The Tenochca, after decades of being pushed around by larger groups, had finally settled in the city of Tenochtitlan, an emerging city-state located on an island in Lake Texcoco in the Valley of Mexico, which they shared with their sister city Tlatelolca2. They were becoming established and were known as strong warriors, but still lacked political clout in the region. Acamapichtli was going to fix that.

We don't know when Acamapichtli was born3, but we do know something about his parents and lineage; arguably, these are the most important things about him. He was a descendant of two noble families, the son of a highborn Tenochca Lord named Opochtli Iztahuatzin who had married Atotoztli I, the daughter of the tlatoani (named Coxcoxtli) of the powerful city-state of Culhuacan. (The Colhua had been pushing the Mexica around for decades.) His mother was also descended from the defunct-but-respected Toltec, giving him a semi-mythic quality.

This bloodline was certainly a factor in his political rise. He was called from his mother's home in Texcoco to serve as cihuacóatl ('governor') of Tenochtitlan, where he was greeted with great ceremony. Making Acamapichtli their governor was a political coup for the city, and even more so due to his marriage to Ilancueitl, a princess of Culhuacán4. Through his Colhua heritage and marital ties he gave the Mexica royal line a recognized connection to the Toltec and their patron deity Quetzalcóatl. He would also take a wife from each of the local districts, to help cement local ties and perhaps also because his first wife had been unable to provide him with a heir.

In 1382 he was crowned as tlatoani, in a ceremony in the temple of Huitzilopochtli, a move that would eventually help make Huitzilopochtli one of the central gods of the Aztecs. The act of instating a tlatoani was essentially a declaration of independence, although as they were living on an island surrounded by swampland that no-one powerful really wanted, and as they remained a tributary of the Azcapotzalco, this was not really a big deal to anyone but the Tenochca. It was however, a necessary step in the rise of the empire.

Under his leadership Tenochtitlan made a number of important improvements. He is credited with, among other things:

  • Expanding the island into the marshes to the east with significant earthworks.
  • Expanding the city's chinampa system of floating gardens around the island.
  • Starting construction on the Templo Mayor (one of the primary temples of the Aztecs).
  • Maintaining a general policy of not going to war with neighboring city-states, preferring to make peaceful alliances with his neighbors when possible. Many of these alliances involved the Tenochca providing military aid to their neighbors.
  • Helping the Tenochca to become known as such good fighters for the cause of the Azcapotzalco that they were given the right to wage war on their own behalf.

Acamapichtli died in 1395; while we don't know cause of his death, we can assume that it was illness, as he had time to bring the city's leaders together and have them vote on his successor. They chose his eldest son, Huitzilíhuitl, a decision which Acamapichtli apparently approved of. While the position of tlatoani is not necessarily hereditary, all of the Aztec rulers were to be descendants of Acamapichtli; in fact, the fourth tlatoani was also one of his sons, Itzcoatl.


1. Some would say that the founder of the Aztec empire was actually Tenoch, the perhaps mythical leader who led the Tenochca to settle on Tenochtitlan.

2. Lake Texcoco has since been mostly drained, but the island was in the area now occupied by the Cuauhtémoc borough Mexico City.

3. Various sources give the date as 1299, 1307, and some as late as 1357.

4. It appears that he was married to Ilancueitl before he was made governor, but history is fuzzy on this point.