III.

Origins and Growth of the Aztec Empire

The group that eventually founded the Aztec Empire, the Mexica, migrated to the Valley of Mexico in the middle of the 13th century. As late arrivals, the Mexica, a hunter-gatherer people, were forced by other groups in the valley to take refuge on two islands near the western shore of Lake Texcoco (one of the five lakes in the area). The Mexica believed in a certain legend, which held that they would establish a great civilization in a marshy area, where they would first see a cactus growing out of a rock with an eagle perched on the cactus. After the Mexica arrived at the swampy site on the shore of Lake Texcoco, their priests proclaimed that they had seen the promised omen. The site turned out to be a strategic location, with abundant food supplies and waterways for transportation.

The Mexica began farming for a living, and in 1325 they founded the city of Tenochtitlán on one of the lake islands. For the next 100 years they paid tribute to stronger neighboring groups, especially the Tepaneca of the city-state of Azcapotzalco, whom they served as mercernaries.

As the Mexica grew in number, they established superior military and civil organizations. The Mexica of Tenochtitlán formed a triple alliance with the city-states of Texcoco and Tlacopan. In 1428 the triple alliance defeated the Tepaneca. Under the Mexica ruler Itzcoatl, his successor Montezuma I, and the Texcocan ruler Netzahualcóyotl, the three states waged a series of conquests. They eventually established an empire that extended from central Mexico to the Guatemalan border and included many different states and ethnic groups, who were forced to pay tribute to the alliance. Tenochtitlán became the dominant power within the alliance.