Clark County, Illinois

Clark County is a county in the southeastern part of U.S. state of Illinois, along the Indiana state line. As of the 2020 census, the population was 15,455. The county seat is Marshall. The county was founded in 1819 and named for George Rogers Clark, an officer who served in the American Revolutionary War.Perrin, p. 237

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Category:1819 establishments in Illinois
Category:Illinois counties