More precisely, the izalcans were one of the four branches of the nahuats who settled in the region, along with the cuzcatlecos, nonualcos, and mazahuas. They were also part of a group of city-states that the Spanish called Tecpán-Izalco, which comprised 15 settlements. The most notable among them were Izalco, Caluco, Nahulingo, and Tacus-calco.