Teotihuacán: founded by the Quiché, Olmec and Zapotec. It was the double island city. Teo meant island in that day’s Quiché Maya. Tihuacán is a Zapotec word and refers to what was originally Teokan, or island of learning. The name Tihuacán is similar to the city of Tehuacán, Puebla, founded by a sister people of the Zapotecs, most likely the Otomi. And it is similar to the Zapotec-named Tehuantepec isthmus. A further namesake, founded by other Zapotec cousins, is the site of Tiahuanaco, in Bolivia.
The original Zapotec island, Teokan, was located at the present-day island of Monte Cristo at the mouth of the Rio Lempa in El Salvador. Over thousands of years, the name Teokan evolved into Tihuacán, as evidenced by the nearby Tehuacán site about ten miles north of Monte Cristo. Monte Cristo and the Bajo Lempa were the home of the pre-Zapotecs before they moved to the Oaxaca Valley.
In summary, Teotihuacán is the double island city because it takes its name from two islands in El Salvador: Teokan or Monte Cristo and Teopan, the Quiché island inside of Tammakchan (now called Lago Coatepeque).By 1000 BCE, the Quichés, Olmecs, and Zapotecs all had a presence in the Valley of Mexico or nearby valleys. First, the Quichés moved to the Valley and founded the chiefdom of Tlatilco, from their island home of Teacapan in northwest Mexico by no later than 1500 BCE. They had been banished from Teopan in about 2200 BCE due to the outbreak of pellegra. Ironically their banishment left them in perfect position to co-found one of the greatest cities.
The Olmecs established Tlapacoya a little after the Quichés arrived and quickly rebuilt a close relationship. The Zapotecs were the last of the three groups to arrive.
It is no surprise these three great nations would come together at Teotihuacán. For thousands of years they lived together in El Salvador, coming together in a conacaste (Maya) or guanacaste (Lenca) celebration each year – the council of the brotherhood, the guanaco.
Between 200 CE (Common Era) and 650 CE Teotihuacán was one of the largest cities in the world, peaking at perhaps 200,000 people. While its founders may have been Quiché, Olmec and Zapotec, by 500 CE a new language was spoken there, Nahuatl. By the end of Teotihuacán in 700 CE, a new people, the Toltecs, was formed. They were mostly Quiche, but also contained some of the other two founding nations and also tribes from northern Mexico who were attracted by the great city.
Teotihuacán maintained close ties with the Olomeka (Olmec) Gulf Coast, the Oaxaca Valley at Monte Alban, and with the Quiche-Pocomam city of Kaminaljuyu. In addition, other Quiche settlements were made along the Pacific Coast of Guatemala and these maintained close ties with Teotihuacán. Especially close ties were maintained with the Ch’orti sites of Chalchuapa and San Andres, at least up until the Ilopango eruption of 200-250 CE, and with the Olomeka-Lenca sites of Tehuacán and Quelepa in central and eastern El Salvador.