Jefferson County, Illinois
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About Jefferson County
Jefferson County is a county located in the southern part of the U.S. state of Illinois. According to the 2020 census, it has a population of 37,113. The county seat is Mount Vernon. Jefferson County also constitutes the Mount Vernon micropolitan area, anchored by the city of Mount Vernon. It is located in the southern portion known locally as "Little Egypt". The western border of the county adjoins the Greater St. Louis consolidated metropolitan statistical area, the Metro-East region, and the St. Louis commuter region and market and television viewing area.
Description adapted from Wikipedia, CC BY-SA 4.0.
Jefferson County at a glance
- County seat
- Mount Vernon
- Population
- 37,113 (2020)
- Land area
- 584 sq mi
- Founded
- 1819
Largest communities in Jefferson County
- Mount Vernon County seat14,600
- Mount Vernon Township12,576
- Centralia12,182
- Shiloh Township6,524
- Dodds Township2,690
History of Jefferson County
The first settler in Jefferson County is believed to have been Andrew Moore. In 1810, he settled near the southeast corner of the county, near where the Goshen Road emerges from the forest of Hamilton County into what is now known as Moore's Prairie. Moore arrived from the Goshen Settlement, near Edwardsville. His migration was therefore retrograde, from the west toward the interior of the State. In 1814, Andrew Moore departed with his eight-year-old son for Jordan's settlement, a journey from which he never returned. A skull that was believed to have been Moore's was found several years later about two miles from his cabin. Jordan's Settlement, also called Jordan's Fort, was southeast of modern Thompsonville, Illinois, about twenty miles south of Moore's cabin. This episode occurred during the War of 1812 when many of the Indian tribes were allied with the British.
Adapted from Wikipedia, CC BY-SA 4.0.
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