Formed in January 1825. The original county boundaries were expansive, reaching from the Illinois River to the Wisconsin border.

Offers historical information, genealogical queries, and maps. Part of the USGenWeb Project.

History, raw data, genealogy statistics, biographies, cemeteries, census, and related historical and genealogical information.

Provides a brief history and links related to the state's smallest county, encompassing only 166 square miles.