It was built by the Mississippian culture, which reached its peak in the region about AD 1100 – 1200 at the nearby major center of Cahokia, a designated UNESCO World Heritage Site within the present-day boundaries of Collinsville.

Cahokia Mounds State Historic Site () is located on the site of an ancient Native American city ( c. 600 – 1400 CE ) situated directly across the Mississippi River from modern St. Louis, Missouri.

The population of Cahokia dispersed early in this period ( 1350 – 1400 ), perhaps migrating to other rising political centers.

" Two convents were established – one in Cahokia, Illinois, which closed in 1855, the other in Carondelet, a village on the outskirts of St. Louis, Missouri.

Located at the Cahokia Mounds UNESCO World Heritage Site near Collinsville, Illinois, its size was calculated in 1988 as about 100 feet ( 30 m ) high, 955 feet ( 291 m ) long including the access ramp at the southern end, and 775 feet ( 236 m ) wide.

* c. 600 BC — Beginning of the construction of the largest Mound at Cahokia, near East St. Louis, Illinois.

Monks Mound, located at the Cahokia Mounds UNESCO World Heritage Site near Collinsville, Illinois, is the largest Pre-Columbian Earthworks ( archaeology ) | earthwork in America north of Mesoamerica.

The most complex society was the Mississippian culture, which reached its peak around 1100 AD and built a large city at Cahokia, near present-day Collinsville, Illinois.

Cahokia was located in a strategic position near the confluence of the Mississippi, Missouri and Illinois rivers.

Mississippian culture pottery and stone tools in the Cahokian style were found at the Silvernale site near Red Wing, Minnesota, and materials and trade goods from Pennsylvania, the Gulf Coast and Lake Superior have been excavated at Cahokia.

As a consequence, many architectural and archeological resources were lost to flooding and destruction of early French colonial villages originally located near the river, such as Kaskaskia, St. Philippe, and Cahokia, Illinois, and old Ste.

Middle Mississippian cultures, especially the Cahokia polity located near East St. Louis, Illinois, was very influential on neighboring societies.

* Moundville: Ranked with Cahokia as one of the two most important sites at the core of the Mississippian culture, located near Tuscaloosa, Alabama.

Monks Mound, built c. 950-1100 CE and located at the Cahokia Mounds UNESCO World Heritage Site near Collinsville, Illinois, is the largest Pre-Columbian Earthworks ( archaeology ) | earthwork in America north of Mesoamerica.

Archaeologists working at Cahokia, the largest Mississippian culture settlement located near the modern city of St. Louis, found distinctive and relatively rare pottery beakers dating from 1050 to 1250 CE.

Cahokia, the urban center of the pre-Columbian Mississippian culture, was located near present-day Collinsville, Illinois.

The region is bordered by tall bluffs such as this one, rising near Cahokia, Illinois.

Numerous cities were built ; Cahokia, the largest, was based in present-day Illinois, and may have had 30, 000 residents at its peak about 1250 AD.

Increased population density gave rise of urban centers and regional chiefdoms, of which the greatest was the settlement known as Cahokia, in present-day Illinois.

What are today know as the Five Civilized Tribes originated in the Southeast part of the United States, and were probably descendents of the Mississippian culture, an agrarian culture that grew crops of corn and beans, with urban centers and regional chiefdoms, of which the greatest was the settlement known as Cahokia, in present-day Illinois.

The Mississippian culture rulers organized thousands of workers to construct villages and complex earthwork mounds at what later became St. Louis and East St. Louis, as well as the urban complex of Cahokia to the north of East St. Louis within present-day Collinsville, Illinois.

For instance, the Mississippian culture, reaching a peak about 1150 at Cahokia in present-day Illinois, had sites throughout the Mississippi and Ohio river valleys, and into the Southeast.

It lost most of its southern lands in the formation of Randolph County in 1795, necessitating the transfer of the county seat to Cahokia, but would expand to the north to take in northwest present-day Illinois and most of present-day Wisconsin in 1801 after becoming part of Indiana Territory.

The chief center of a Middle Mississippian settlement is at Cahokia, in present-day Illinois, a city that at its peak had 20, 000-30, 000 people.

Cahokia, located in present-day Collinsville, Illinois, was the major regional center of this culture.

By the mid-18th century, the major settlements included Cahokia, Kaskaskia, Chartres, Saint Philippe, and Prairie du Rocher, all on the east side of the Mississippi in present-day Illinois ; and Ste.

The first interaction with other tribes occurred during this period: artifacts from the major regional chiefdom and urban complex of Cahokia, at present-day Collinsville, Illinois, have been recovered at Illinois River sites.

The Fort Ancient culture was influenced by the contemporary Mississippian culture society based along the mid-Mississippi River valley with its North American center at Cahokia ( in present-day Illinois ).

The expansion of the great metropolis and ceremonial complex at Cahokia ( in present-day Illinois ), the formation of other complex chiefdoms, and the spread and development of SECC art and symbolism are characteristic changes of this period.

The best-known flat-topped pyramidal structure, which at over 100 feet ( 30 m ) tall is the largest pre-Columbian earthwork north of Mexico, is Monks Mound at Cahokia Indian Mounds in present-day Collinsville, Illinois.

The largest earthen work step pyramid of this type in North America is Monk's Mound, located in present-day Cahokia, Illinois.

Several French colonial towns of the Illinois Country, such as Kaskaskia, Cahokia and St. Philippe, Illinois were flooded and abandoned in the late 19th century, with a loss to the cultural record of their archeology.

Genevieve was originally an off-shoot of the older French communities on the east bank of the Mississippi River — Cahokia, Kaskaskia, village of Chartres, Prairie du Rocher, and St. Philippe.

This name had been supplied by the French to a spring of water a mile south of the site of Waterloo, at which they had doubtless often camped on their journeys between Kaskaskia, Cahokia, and St. Louis.

Cahokia is a village in St. Clair County, Illinois, United States.

Later, Cahokia was named the county seat of St. Clair County.

When in 1801 St. Clair County was enlarged, Henry Harrison named the Cahokia Courthouse the legal and governmental center of a sizeable area extending to the Canadian border.

Cahokia is home to the St. Louis Downtown Airport, a general aviation facility.

Returning to the Illinois Country, Pontiac was murdered on April 20, 1769, at the French village of Cahokia ( nearly opposite St. Louis, Missouri ) by a Peoria Indian, perhaps in retaliation for an earlier attack by Pontiac.

Pontiac's burial place is unknown, and may have been at Cahokia, Illinois, but evidence and tradition suggest that he was buried in St. Louis.

Until the 19th century a series of similar mounds existed in what is now the city of St. Louis, some to the south west of the Cahokia site.

The unit had members in Alton, Anna, Carolton, Carbondale, Cahokia, East St. Louis, East Carondelet, Edwardsville, Evansville, Grafton, Granite City, Hartford, Jerseyville, Murphysboro, Prairie du Rocher, Quincy, Springfield, and Winchester.

The largest mound site north of Mexico is Cahokia, a vast World Heritage Site located just east of St. Louis, Missouri.

* the Greater Saint Louis Air & Space Museum, located at St. Louis Downtown Airport, Cahokia, Illinois, United States

Much of archeological importance was lost in the flooding and destruction of French colonial towns such as Kaskaskia, St. Philippe, and Cahokia, Illinois ; and Old Mines and old Ste.

On the afternoon of July 5, Captain Bowman was sent with 30 mounted men, along with some citizens of Kaskaskia, to secure Prairie du Rocher, St. Philippe, and Cahokia.

" In 1814, Reynolds opened a law office in the old French village of Cahokia, then the county seat of St. Clair County.

* St. Louis, Missouri, known at one time as Mound City due to the presence of several ceremonial mounds similar to the nearby Cahokia Mounds.

At the same time, the nearly abandoned Fort St. Joseph was raided by Americans from Cahokia.