After Moctezuma I succeeded Itzcoatl as the Mexica emperor, more reforms were instigated to maintain control over conquered cities. Uncooperative kings were replaced with puppet rulers loyal to the Mexica. A new imperial tribute system established Mexica tribute collectors that taxed the population directly, bypassing the authority of local dynasties. Nezahualcoyotl also instituted a policy in the Acolhua lands of granting subject kings tributary holdings in lands far from their capitals. This was done to create an incentive for cooperation with the empire; if a city's king rebelled, he lost the tribute he received from foreign land. Some rebellious kings were replaced by calpixqueh, or appointed governors rather than dynastic rulers.
Moctezuma issued new laws that further separated nobles from commoners and instituted the death penalty for adultery and other offenses. By royal decree, a religiously supervised school was built in every neighborhood. Commoner neighborhoods had a school called a "telpochcalli" where they received basic religious instruction and military training.

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