Teotihuacan at its height: the largest city of the Americas

By about 250 the great monuments of Teotihuacan stood, and the city’s growth had levelled off; the following centuries were its classic age, which archaeologists call Period III (about 350–650). Between about 250 and 350 the seat of power seems to have moved from the Temple of the Feathered Serpent, which was desecrated around 300, to the Avenue of the Dead Complex, and building turned to comfortable stone apartment compounds for the population — changes some scholars read as a shift from a monarchy to a more collective government. No royal palaces or dynastic monuments have been found. About 2,000 buildings filled a gridded city of some 18–21 km² with roughly 100,000 inhabitants — other estimates run to 150,000 or more — which made it one of the largest cities in the world at the time.

The city lived by crafts and exchange: its workshops turned out obsidian tools traded across Mesoamerica, pottery and textiles, and whole neighbourhoods were inhabited by migrants, especially from Oaxaca and the Gulf Coast. Teotihuacan-style buildings, pottery and imagery appear far away, from Veracruz to the Maya area; Maya inscriptions record the “arrival” of Siyaj Kʼakʼ at Tikal in 378 under the auspices of Spearthrower Owl, perhaps a ruler of Teotihuacan. Whether the city ruled an empire or exerted its influence through trade, prestige and religion is still debated. Its mural painting flourished above all in 450–650.

The civic buildings along the Avenue of the Dead were eventually sacked and burned, perhaps in an internal uprising, since no traces of foreign invaders have been found; this destruction is usually dated to around 550, by other accounts to the mid-7th century, and some authors extend the city’s heyday to 650. The population declined, perhaps also because of the droughts that followed the climatic crisis of 535–536. By the mid-8th century Teotihuacan was deserted; centuries later the Aztecs named the ruins “the place where the gods were born”.