What was the Aztec Empire?

The Aztec Empire was the most powerful state in Mesoamerica at the time of European contact, controlling a vast tributary empire from its remarkable island capital of Tenochtitlán, built on Lake Texcoco in the Valley of Mexico. The Aztecs — more properly called the Mexica — had risen from a small, marginalized tribe to become the dominant power in central Mexico in just two centuries.

Tenochtitlán was one of the great cities of the world. With a population of 200,000–300,000, it was larger than any city in contemporary Europe. Built on an island connected to the mainland by causeways, it featured aqueducts for fresh water, enormous public markets, monumental pyramid-temples, and chinampas — artificial agricultural islands that produced food year-round. When the Spanish conquistador Bernal Díaz first saw it, he compared it to the enchanted cities of Amadís de Gaula — a fairy tale.

The empire was sustained by a combination of military power and religious ideology. Subject peoples paid tribute in goods, labor, and sacrificial victims. The Aztec cosmological system held that the sun required human blood to continue its daily journey — a belief that drove an elaborate system of ritual sacrifice and the 'Flower Wars' fought specifically to capture prisoners. This practice, while sensationalized in European accounts, was embedded in a complex theological system.

The empire's rapid collapse between 1519 and 1521 resulted from multiple factors: Spanish military technology (steel weapons, horses, cannons), devastating epidemic diseases (particularly smallpox), and the willingness of subject peoples — resentful of Aztec tribute demands and sacrificial requirements — to ally with Hernán Cortés against their overlords.