Uncovering the First City in Modern-Day America

Construction projects in East St. Louis have revealed the full breadth of Cahokia, the largest city north of the Rio Grande before the arrival of Europeans.

East St. Louis might have one of the highest crime rates in the U.S., and it might have seen two-thirds of its population flee since the 1960s, but a thousand years ago, it was the site of the largest and most cosmopolitan city north of the U.S.-Mexico border. Archaeologists have long known about a settlement called Cahokia that now lies beneath the Illinois city, but only just recently have they pieced together just how big the city would have been. Last year, construction teams discovered all sorts of artifacts and buildings when they were excavating the banks of the Mississippi to construct a new bridge in the area. According to research published in the journal Science, Cahokia was not the temporary encampment that many historians had believed it to be. Rather, it was sprawling, cosmopolitan city, 13 kilometres wide and spanning both sides of the Mississippi River, making it by far the largest city in either Canada or the United States before the arrival of European settlers. (Teotihuacan and Tenochtitlan, both Aztec cities in modern-day Mexico, were significantly larger and more, umm, blood-splattered.) First settled around 1000 AD, Cahokia's residents built hundreds of thatched-roof homes, massive monumental mounds of dirt, and ceremonial plazas. The population at its peak numbered in the tens of thousands, and drew in Native Americans from all around the Mississippi and Great Plains. However, by about 1200, Cahokia's population had been halved, perhaps due to drought, and by 1350, the first North American city had been all but abandoned.