St. Clair County, Illinois
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About St. Clair County
St. Clair County is the ninth most populous county in Illinois. Located directly east of St. Louis, the county is part of the Metro East region of the Greater St. Louis metropolitan area in Southern Illinois, known as "Little Egypt". As of the 2020 United States census, St. Clair County had a population of 257,400, making it the second most populous county in Illinois outside the Northern Third. Belleville is the county seat and largest city.
Description adapted from Wikipedia, CC BY-SA 4.0.
St. Clair County at a glance
- County seat
- Belleville
- Population
- 257,400 (2020)
- Land area
- 674 sq mi
- Founded
- 1790
Largest communities in St. Clair County
- Belleville County seat42,404
- St. Clair Township35,758
- Caseyville Township35,580
- O'Fallon32,289
- O'Fallon Township26,291
History of St. Clair County
This area was occupied for thousands of years by cultures of indigenous peoples. The first modern explorers and colonists of the area were French and French Canadians, founding a mission settlement in 1697 now known as Cahokia Village. After Great Britain defeated France in the Seven Years' War in 1763 and absorbed its territory in North America east of the Mississippi River, British-American colonists began to move into the area. Many French Catholics moved to settlements west of the river rather than live under British Protestant rule. After the United States achieved independence in the late 18th century, St. Clair County was the first county established in present-day Illinois; it antedates Illinois' existence as a separate jurisdiction. The county was established in 1790 by a proclamation of Arthur St. Clair, first governor of the Northwest Territory, who named it after himself.
Adapted from Wikipedia, CC BY-SA 4.0.
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Part of Illinois Voter Check
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