At the height of its power, the Aztec Empire had 38 tributary provinces.
These provinces belonged to the tribute system administered by the Triple Alliance of Tenochtitlan, Texcoco, and Tlacopan, with Tenochtitlan eventually becoming the dominant power. The provinces were expected to provide regular payments, which could include food, textiles, luxury goods, raw materials, and military supplies.
The figure 38 refers to the empire’s organized tributary provinces, not every community under Aztec influence. The empire also contained strategic provinces and other subordinate city-states whose relationships with the Triple Alliance differed. That distinction explains why descriptions of the empire’s size can produce different totals.
Administration was indirect rather than uniformly centralized. Local rulers often remained in place after conquest as long as they delivered tribute and accepted imperial authority. Officials called calpixque supervised collection, while higher-ranking huecalpixque oversaw groups of provinces. Under Moctezuma I, two calpixque were assigned to each tributary province, helping connect provincial collections with storage and administration in Tenochtitlan.