The Aztecs, also known as the Mexica, arrived in Mesoamerica around the beginning of the 13th century. Their arrival helped bring about the fall of the previously dominant Mesoamerican civilization, the Toltecs.
According to legend, the Aztecs were directed by their god Huitzilopochtli to find a settlement in the place where an eagle is perched on a cactus, eating a snake. They drained the swampy land, constructed artificial islands on which they could plant gardens and established the foundations of their capital city, Tenochtitlán, in 1325 A.D. Tenochtitlan is currently known as Mexico City.
In 1428, Itzcoatl- the ruler during that time- formed an alliance with the Texcocans and the Tacubans to conquer powerful rivals in nearby regions. The Aztec empire continued to conquer and grow even after Itzcoatl’s successor Moctezuma I took the throne in 1440. Moctezuma is remembered as the father of the Aztec empire.
“By the early 16th century, the Aztecs had come to rule over up to 500 small states, and some 5 to 6 million people, either by conquest or commerce. Tenochtitlán at its height had more than 140,000 inhabitants and was the most densely populated city ever to exist in Mesoamerica.”
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