Political shifts in Central Mexico around 1401

Timeline

1. 1401–1405Azcapotzalco · Mexico CityAzcapotzalco, the Tepanec capital, increased its tribute demands on vassal city-states, provoking dissatisfaction among the Mexica, Acolhua, and others and raising political tensions in the valley.
2. 1403–1408Tenochtitlan · Mexico CityTenochtitlan accumulated power through chinampa agricultural expansion and military levies, seeking greater autonomy within the Tepanec framework and establishing informal contacts with other discontented vassals.
3. 1408–1410Valley of Mexico · State of MexicoAlliance tendencies among city-states such as Texcoco, Tlacopan, and Tenochtitlan strengthened, and cracks appeared in the Tepanec vassal system, laying the political groundwork for the wars of the 1420s and the Triple Alliance of 1428.