Raye's History House

What are the Cahokia Mounds?

The Cahokia Mounds are a group of mounds on the southern tip of Illinois in Collinsville, 8 miles (13km) northeast of St. Louis. They were created by the Natives who lived in the area between the years 600 and 1400 AD.

The largest mound, called Monks Mound, is the biggest pre-Columbian settlement north of Mexico. Taking up about 12 acres and topping off at 30 meters high, the mound took several centuries to build and and was constructed in 14 stages. Monks Mound contains enough dirt to fill 7,000 tractor trailers and all of this was built by a society that didn’t have the wheel or beasts of burden to help them out. The Cahokia Natives had to move 55 million cubic feet of earth in woven baskets.

The site also contains woodhenge, a circle of posts that were used as an astronomical observatory. The placement of the posts mark the solstices and other astronomical occurrences. More than one woodhenge exists on the site’s grounds.

Who Were the People Who Built the Cahokia Mounds?

The Cahokia mounds were built over a period of 800 years by the Natives who lived on the floodplains of the Mississippi River. At the city’s height, between 1050 and 1150, the area was home to 10,000 to 20,000 people and is believed to have been larger than contemporary London.

Cahokia was once one of the most advanced cities in the world with an extensive trade network. Archeologists have found tattoo kits, balls, dice, and marine shells from the Gulf of Mexico, rocks from the Smokey Mountains, and copper from Michigan. There’s also evidence that the Natives were trading as far north as modern Canada and as far south as Mexico.

The Cahokia Natives were great engineers who knew how to use the environment to their favor. The people who lived there diverted Canteen Creek to bring more water into the city. They also knew how to work with the clay dirt inside the mounds to keep them from breaking. Alternating layers of sand and clay prevents air and moisture from entering the soil and causing it to expand and contract.

The people of Cahokia also built homes and other structures on top of and near the mounds. Monks Mound was thought to have held a large structure that most likely belonged to the priests and chiefs. Wide plazas for merchants, ball courts, and playing fields for a popular game called Chunkey were spread out across the land, making the city surprisingly modern in its layout.

Mounds were used for religious services, which people came from miles around to participate in. Tobacco smoking was a popular activity during the religious practices of the area’s animists.

Since the mounds would have been huge projects (even one of the smallest mounds would have taken a large workforce 10 years of daily work to complete), Cahokia probably had a strong central authority. The community’s social pyramid was most likely stratified with chieftains on the top, followed by sub-chiefs and priests, then other elites like clan and local leaders, and, finally, everyone else.

The city began to decline after the 1200s and was completely deserted by 1400. Reasons for this may have included, deforestation, overpopulation, and disease. Floods are also common in the area and may have advanced the city’s demise. Furthermore, an earthquake that hit in the 13th century, when the city began to decline, toppled several buildings. Human sacrifice at the end of the city’s life means that the Natives may have tried to save their city through these means.

Cahokia Rediscovered

Cahokia was discovered by Europeans for the first time in the 1600s when French explorers entered the area. At first, like most awe-inspiring structures in the world, Europeans did not believe that Native Americans could have built the Cahokia Mounds. Instead, other explanations that were offered were:

• Built by the Chinese
• A natural occurrence
• Built by the Welsh or Phoenicians
• Created by the same people who supposedly built Atlantis
• Made by Swedish immigrants in North America
• And, Cahokia was attributed to multiple people in the Bible

Also, like many ancient cities in conquered lands (from Mesa Verde to Great Zimbabwe), Cahokia was looted by the people who colonized Illinois.

Cahokia was granted protection by the U.S. government in 1925 and formal excavations finally began in the 1960s. By 1964, Cahokia became a National Heritage Site and in 1982 was designated as a UNESCO World Heritage Site.

Today, the mounds face threats to their longevity, such as erosion, nearby development, flooding, and damage from deep rooted plants.

Other Sites Like Cahokia

Although the Cahokia mounds stand out as a massive feat of engineering, they aren’t necessarily oddities. The oldest mound that has been found in the United States is Ouachita in Louisiana, which dates back 5,400 years ago.

Other mounds in the United States are shaped like cones, stepped pyramids, birds, lizards, and beans. Another mound that stands out is the 1,330 foot long serpent in Peebles, Ohio.

Bonus Facts:

• Despite the mounds using mass amounts of labor to finish them, there is no evidence of slavery.
• Cahokia was built on fertile land where corn, squash, and beans were grown.
• Current deforestation and erosion has led to more flooding in the Midwest which threatens the site.
• Natives had repopulated Cahokia by the late 1600s, but there is no consensus on rather they are the descendants of the Natives who built the city.
• Many of the mounds were surrounded by watchtowers and other defensive structures.

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