Cahokia, Illinois

Cahokia is a settlement and former village in St. Clair County, Illinois, United States, founded as a colonial French mission in 1689. Cahokia is on the east side of the Mississippi River in the Greater St. Louis metropolitan area. As of the 2010 census, it had a population of 15,241. On May 6, 2021, the village was incorporated into the new city of Cahokia Heights.

The name refers to one of the clans of the historic Illiniwek confederacy, who met early French explorers to the region. Early European settlers named the nearby (and long-abandoned) Cahokia Mounds in present-day Madison County after the Illini clan. The UNESCO World Heritage Site and State Historic Park were developed by the Mississippian culture, active here from 900 to 1500 AD. A connection to the clan is possible but unknown. The area was part of an extensive urban complex, the largest of the far-flung Mississippian culture territory through the Mississippi and Ohio River Valleys.

French Canadian colonists founded Cahokia village in 1696 as a Catholic mission. The historic Church of the Holy Family is the oldest continuously active Catholic parish in the United States, as well as the oldest church west of the Allegheny Mountains. Other significant colonial and Federal-period buildings listed on the National Register of Historic Places include the Cahokia Courthouse (circa 1740, in the French Colonial style); and the Jarrot Mansion (circa 1810).

Archeologists ascribe the earthwork mounds Cahokia complex to the Mississippian culture, an earlier indigenous people, who are not believed to have been ancestral to the Illini. The city site reached its peak in the 13th century and was abandoned centuries before European contact. The Cahokia Native Americans of the Illinois did not coalesce as a tribe and live in the Illinois area until nearly the time of French contact 300 years ago.

Father Pinet founded a mission in late 1696 to convert the Cahokian and Tamaroa Native Americans to Christianity. Pinet and the Seminary of Foreign Missions of Quebec built a log church and dedicated it to the Holy Family.

Over the next 100 years, Cahokia became one of the largest French colonial towns in the Illinois Country. It was centrally located for trading Indian goods and furs, and grew to about 3,000 inhabitants. Its thriving business district reflected a frontier society numerically dominated by men, as it had 24 brothels. The nearby town of Kaskaskia on the Mississippi River (founded 1703) became the region's leading shipping port, and Fort de Chartres (founded 1718) was developed by the French as a military and governmental command center. The 50-mile (80 km) area of land between the two villages was cultivated by farming settlers, known as habitants, whose main crop was wheat. As settlement expanded, the relationship between the settlers and the Indians continued to be peaceful. Settlers were mostly Canadien migrants whose families had been in North America for a while.

Cahokia declined after the French lost the French and Indian War in North America to the British in 1763, as part of the broader Seven Years' War in Europe. Only Fort Kaskaskia (built 1733) was destroyed in the conflict, and Cahokia remained regionally important for another four decades. In the treaty ending the war, France ceded large parts of what it called the Illinois Country east of the Mississippi River to the British, including the area of Canada. Many French-speaking residents of Cahokia and elsewhere in what had been Upper Louisiana moved west of the river to territory still controlled by the French rather than live under British rule. Many moved to Lower Louisiana, where they founded new Canadien villages on the west side of the Mississippi River, such as Ste. Genevieve, Missouri, and St. Louis.

The Odawa leader Pontiac was assassinated by other Indians in or near Cahokia on April 20, 1769.