Aztec domination reaches into most of central and southern Mexico by the early sixteenth century (with the exception of the Mayan areas in the southeast).

Before the settlement at Tenochtitlan, Aztec society was quite simple in its organization and was composed of peasants, warriors, and priest-rulers.

Afterward, and with a much larger population, there is an increasing division of labor and a more complex social structure.

The emperor is selected according to merit from among the ruling dynasty.

The nobility is composed of the high priests, the military, and political leaders.

The merchant class lives apart in the city and has its own courts, guilds, and gods.

Commoners, the largest segment of society, are farmers, artisans, and lower-level civil servants.

The lowest rung of society is composed of conquered peoples brought to Tenochtitlan as slaves.

The political structure of the Aztec empire is based on a loose coalition of city-states under the fiscal control of Tenochtitlan.

The main objective of Aztec expansion is to exact tribute from conquered peoples.

Tributes are in kind: cocoa, cotton, corn, feathers, precious metals and stones, shells, and jaguar skins are among those sent.

The towns also have the obligation to provide soldiers and slaves and to recognize Aztec supremacy and the supremacy of the Aztec god Huitzilopichtli.

Otherwise, towns are basically free to conduct their internal affairs, and Aztec hegemony is never fully consolidated—a fact that will eventually become a major element in the fall of the empire.