The Mexica City of Tlatelolco was founded in the year 1338, according to the chronicles, after a separation of the Tenochca group, who stayed in Tenochtitlán, and the Tlatelolca group that sought a settlement further north. It enjoyed independence until 1473, when after fighting with the Mexica it became dependent on them. Its great flea market became the center of commerce for both islands—already cordially united—as well as for the Triple Alliance, made up of Tenochtitlan, Texcoco and Tlacopan (Tacuba).

Unlike the four neighborhoods of its neighbors, Tlatelolco was divided into 19 neighborhoods (one of which was the brave Tepiton), and in them its cosmopolitan personality was evident, due in part to the influx of merchants coming from distant lands, as well as the very active pochtecas, local merchants who had particular laws, their own governor and who took their expeditions to the arid north, the Soconusco and the current Nicaragua.