is a city in St. Clair County, Illinois, United States. The population was 41,410 at the 2000 census. It is the county seat of St. Clair County, and the seat of the Roman Catholic Diocese of Belleville and the National Shrine of Our Lady of the Snows. Belleville, located within Southern Illinois, is included in the Metro-East region of the St. Louis Metropolitan Area. Belleville's sister city is Paderborn, Germany.
George Blair named the city of Belleville in 1814. Blair was born in 1760. Blair's family was of Scottish ancestry; his father was born in Scotland. Blair donated an acre of his land for the Town Square and an additional that adjoined the Square for the new County Seat, thereby replacing the old county seat in Cahokia, Illinois. Belleville was incorporated as a village in 1819, and became a city in 1850. Although the name "Belleville" is French for "Beautiful City", most of the population is of a German heritage. After the failure of the German Revolution in the 1840s, many of the educated fled their homeland. Belleville was the center of the first important German settlement in the State of Illinois. At this time, an estimated 90% of the city's population was either German born or of German descent.