If you thought we, as Americans, have a great grasp on our continent’s history and its inhabitants over the last 1,000 years or so, then you thought wrong. Take the Cahokia Mounds State Historic Site — the remains of a Native America city founded around 600 CE, located in present-day Illinois and Missouri. We know that a complex and sophisticated society once existed here, complete with markets, meeting places, advanced agricultural processes, complex architecture, skillful artwork, and numerous large, earthen mounds. What we don’t know, however, is what became of the some 40,000 inhabitants.
For unknown reasons (overhunting, deforestation, and flooding have been proposed), the population declined in the thirteenth century, and by 1300 the site was totally abandoned. To reiterate, the city of Cahokia went from boom to bust in under a century — and this event only occurred 700 years ago. To give you an idea of the magnitude of this lost civilization, it’s worth mentioning that Cahokia remained the largest city ever built in the United States up until the 1780s, when Philadelphia’s population expanded beyond 40,000 people.