Cahokia Mounds State Historic Site is located near Collinsville, Illinois, around eight miles east of St. Louis. The site consists of over a dozen prehistoric mounds constructed by a vanished culture around the time Leif Ericson’s longships landed in Vinland. The mounds were built by a group of people identified by anthropologists as belonging to the Mississippian Culture. Not much is known about them, other than the artifacts and earthen structures they left behind.
The most prominent is Monk’s Mound. Monk’s Mound was the largest earthen structure north of central Mexico at the time of its construction. “Begun around A.D. 900 and completed 300 years later,” Gene S. Stuart wrote in his book America’s Ancient Cities (1988). “It has 4 terraces; rises 100 feet; covers some 16 acres with a base measuring approximately 700 by 1,080 feet, and contains about 22 million cubic feet of earth.” A large building sat at the summit of the mound.
The mounds were a part of a large city, which reached the height of its power between 1000 and 1200 A.D. A stockade surrounded the central structures at the site, which the residents rebuilt several times. There is no evidence of a battle at the location and it’s unknown whether the city had any enemies.
Cahokia stood at the hub of a network of “mound communities,” which would have reinforced its role as a trade center along with its place at the juncture of the Mississippi, Illinois, and Missouri Rivers. It maintained that position for several hundred years before the site was mysteriously abandoned around 1400 A.D. In comparison, the city of St. Louis has been in existence for a little over 200 years.
Cahokia was not the only mound city in North America. According to Earl H. Swanson, in his book The Making of the Past: The Ancient Americas (1989), similar, but less extensive cities have been found near Spiro, Oklahoma; Etowah, Georgia; Moundville, Alabama; and Hiwassee Island, Tennessee. Many of these mounds were used for burial, and contain human remains, stone tools, weapons, pottery, and artwork.
Located farther north at the juncture of the Illinois and Spoon rivers, Dickson Mounds was also a settlement site of Mississippian Indians. Recently, archaeologists from the Dickson Mounds Museum discovered evidence of a 700 year old settlement near the mounds, which included pottery shards, arrowheads, and human bones.
At the time the first French explorers began to explore the Illinois country, the native peoples had no knowledge of this long-vanished culture.
In the 1800s, American archaeologists believed some earlier race, distinct from American Indians, constructed the mounds. They called them, appropriately enough, the “Mound People” or the “Mound Builders.” They assumed that the Native American tribes had exterminated them some time in the distant past.
Many of Illinois’ familiar tales are only a few decades old, but people lived on that land for over a thousand years. The Cahokia Mounds are a reminder that recorded history only tells a small part of the story.