Ten Mysterious Facts Americans Need To Know About America’s Largest Ancient City


We are W. Michael Gear and Kathleen O’Neal Gear, archaeologists and anthropologists by academic training and professional inclination. That we are New York Times and international bestselling authors with fifty-six books in print is almost incidental. We’re best known for writing about the archaeology of the Lost Continent. Which Lost Continent? Why, our own of course: North America’s.

Our latest book, Sun Born, is the second in a trilogy about the great city of Cahokia. Ever heard of it? Know where it is? If you don’t, you’re not alone. The ancient Cahokia metroplex lies under the modern city of St. Louis, Missouri, and extends east across the Mississippi to the Illinois uplands. More Americans are familiar with the ancient city of Angkor Wat in Cambodia than Cahokia in their own country.

At its peak around 1150 C.E., Cahokia was so large that a contemporary London, Paris, and Budapest could have been placed within its borders with room left over. Nothing in Europe would have compared.

So, if Cahokia was so important, so huge, and so sprawling, why haven’t more Americans heard about it?

Fact No. 1: Unlike other cities that were built of stone, Cahokia was built out of earth, timbers, and thatch. The great five-story temples, sprawling clan houses, and palaces were either burned or rotted away over the centuries. Today when you go to visit Cahokia, all that remains are the earthen mounds that served as foundations.

Fact No. 2: Who were the Cahokians? Evidence indicates they were indigenous Native Americans, and their descendants are the modern Dhegiha Siouan peoples now known as the Osage, Omaha, Ponca, Quapaw, and Kansa.

Fact No. 3: Cahokia was a preplanned city—surveyed, laid out, and built with specific spatial relationships. Using a standard unit of measure 47.5 meters in length, the entire city grid is laid out at an azimuth of 005 degrees.

Fact No. 4: The entire city is laid out as a lunar calendar. The Cahokians regulated their lives by the 18.6-year lunar cycle, calculating both the maximum and minimum lunar rises and settings. In addition, they built “Woodhenge,” which is a huge, circular observatory from which the Cahokians precisely monitored the movements of the sun, moon, and stars.

Fact No. 5: Like ancient Rome, Cahokia was an imperial city whose colonies and influences extended from sites like Trempealeau, Wisconsin, in the north to the Carolinas in the east, and throughout the Deep South. Also like Rome, Cahokia left its imprint on the peoples and beliefs of the entire continent.

Fact No. 6: Cahokia drew people from all over the central United States. It literally exploded on the landscape, having drawn tens of thousands of people who picked up entire villages to move to Cahokia and participate in the building, rituals, and chunkey games. Why? One explanation—and the one we use in our books—is that the Cahokians “reincarnated” the celestial hero Morning Star.

Ten Mysterious Facts Americans Need To Know About America’s Largest Ancient City     Fact No. 7: How did so many people support themselves? For one thing, Cahokia was located in one of the richest agricultural environments in the world, at the junction of the Mississippi, Missouri, and Illinois Rivers and just above the confluence of the Ohio River. Not only was farming corn and squash productive and the forest rich in nuts, but the river system allowed for the importation of food by the canoe load. In addition, the city rested along the major migratory flyway for ducks, geese, and herons, not to mention the riparian harvest of fish, turtles, and freshwater mussels and clams. Deer, turkeys, squirrels, opossum, elk, and bison, their bones now lying in trash pits, were brought in from outlying areas.

Fact No. 8: What on earth is chunkey and why was it important to the Cahokians? In the recorded stories throughout the Midwest, it was said that during the Beginning Times, Morning Star’s father played chunkey with giants and lost his head. When he became a man, Morning Star went to play the giants and won, taking their heads and bringing his father’s back to life. To play the game, a disc-shaped stone is bowled down a court, and the players seek to hit it with thrown lances. Chunkey wasn’t just a game, but a religious experience that helped to glue the disparate peoples of Cahokia together.

Fact No. 9: How long did Cahokia last? The “Big Bang” started at around 1050 C.E. and reached its maximum by the mid-1100s. Cahokia was smaller through the 1200s, and the core areas were protected by high, bastioned walls. In 1270, East Cahokia was burned. In the 1300s, much of the outlying areas were abandoned; only the core was still occupied. By 1400, Cahokia was essentially abandoned. In fact, archaeologists refer to the area as “The Vacant Zone.”

Fact No. 1: Why did Cahokia fail? Religious states are always built on a promise: The people will work and sacrifice to the gods, and in return, the gods will ensure the people’s prosperity. The deal held during what we call “The Medieval Warm Period,” but with the beginning of what’s known as “The Little Ice Age,” it all came tumbling down.