The Lost Culture of the Mississippian Floodplain

Before Columbus, one of the largest and sophisticated cities of America, rivaling even some of the largest cities in Europe, thrived on the floodplain of the Mississippi. This powerful culture influenced surrounding ones from the Great Lakes to the Gulf of Mexico. And then, suddenly, they all disappeared.

Entering the Cahokia Mounds State Historic Site, viewing Monk's Mound
[Northfielder/Flickr]

During the Mississippian period (800-1400 CE), Cahokia, located in southwest Illinois (just outside of St. Louis), had around 120 mounds which covered nearly 1,600 hectares. This is the largest pre-Columbian archaeological site in North America north of central Mexico, as well as the earliest. According to UNESCO, Cahokia is an exceptional example of pre-urban structuring. Also, "it is the pre-eminent example of a cultural, religious, and economic center of the prehistoric Mississippian cultural tradition." The size and layout of this pre-urban society is evidence of the powerful political and economic system that was in place, which can be held responsible for organization of labor, trade, and agriculture.

Cahokia was larger than London in 1250 CE. The Mississippians built a variety of structures: from practical homes to monumental public works that still remain. The agricultural society may have had a population of 10,000 - 20,000 at its peak (1050-1150 CE). And though this culture left us no writing, we have mounds.

Meet the Mounds

What They're Made Of

The Cahokia used earth and wood for their architecture. Examples of this can be seen in their mounds and in their homes. Wooden palisades encompassed many zones which were possibly defensive enclosures; this is seen at Monk's Mound and the entire central section of the site. Red ochre was found in postholes which may suggest that ochre was used as paint.

Monk's Mound & The American Woodhenge

Monk's Mound is the largest prehistoric earthwork in the Americas. It covers over 5 hectares and is 30 meters tall. This mound is where the leader of the community resided. In the early 1960s, Dr. Warren Wittry discovered a series of large oval-shaped pits, which later revealed fragments of red cedar (considered a sacred wood) that served as posts. Dr. Wittry named this Woodhenge. The posts mark the sunrises during the equinoxes with the front of Monk's Mound.

Monk's Mound
[reallyboring/Flickr]

Woodhenge
[Nathaniel Paluga (Drpaluga)/Wikimedia Commons CC-BY-SA 3.0]

Fox Mound & Round Top

The mounds known as Fox Mound and Round Top (also known as Moorehead's Mound) seem to have been joined by a platform (though, it's equally possible the mounds blended together over time). Fox Mound, at 14 meters tall, is a flat-top platform mound that has never been excavated. It's companion, Round Top, is a true conical mound about 13.4 meters tall which is also untouched. These two mounds retain much of their original forms today.

Fox Mound
[Lance and Erin/Flickr]

Round Top
[Lance and Erin/Flickr]

Fox Mound (left) and Round Top (right) as seen from the top of Monk's Mound
[jmehre/Flickr]

The Site Outskirts

Around the edges of the site lie the remains of resential quarters, areas for specialized activity, and public ceremonial areas. The living areas had small gardens, but the agricultural lands are found beyond the city-limits as well as small satelitte villages.

A diorama showing a Mississippian potter [LEFT] and woman grinding maize with a stone mortar [RIGHT],
from the Cahokia site museum.
[Herb Rose/Wikimedia Commons CC-BY-SA 3.0]

The Mystery of Cahokia

Where did the people of Cahokia go? Did other tribes absorb them? Did they create new tribes? Many questions remain unanswered about the Cahokians. The decline of their civilization may have begun around 1200 CE - we know that by the 1400s they were gone. Perhaps they depeleted their resources and were forced to move...war may have struck...maybe it was a disease. Political and economic power may have declined. We know they were a thriving community that made significant advances in astronomy, agriculture, and economics which probably spurred development in other regions of America.

Cahokia Today

Despite the four lane road that runs cuts through the site, Cahokia Mounds is one of eight cultural World Heritage sites in the United States. Ten miles away, only one mound remains. About 890 of the 1600 hectare site is protected. Of the 120 mounds, 109 have been recorded and 68 of those lie within the protective range of Cahokia Mounds State Historic Site. The rest lies under urbanization. Few know of the existence of Cahokia outside of St. Louis, IL. We may only see piles of dirt, but these piles of dirt tell one of the oldest stories of our American heritage.

For Further Reading

Cahokia Mounds State Historic Site :: www.cahokiamounds.org

Cahokia, America's Forgotten City (National Geographic) :: ngm.nationalgeographic.com

UNESCO Cahokia Mounds :: whc.unesco.org