Belleville (French: Belle ville, meaning "Beautiful city") is a city in St. Clair County, Illinois, United States. As of the 2010 census, the city has a population of 44,478. It is the eighth-most populated city outside of the Chicago Metropolitan Area and the most populated city south of Springfield in the state of Illinois. 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 is the most populated city in the Metro-East region of the St. Louis Metropolitan Area and in Southern Illinois.
George Blair named the city of Belleville in 1814. Blair was born in 1760 and his father was born in Scotland. Blair donated an acre of his land for the Town Square and an additional 25 acres (100,000 m2) that adjoined the Square for the new County Seat, causing the county seat to be transferred from the village of Cahokia. Belleville was incorporated as a village in 1819, and became a city in 1850. It is said that Blair named the city Belleville (French for beautiful city) because he believed that a French name would attract new residents. Since major immigration in the mid-19th century following revolutions in Germany, most of the population is of German heritage.
After the failure of the German Revolution in 1848, many of the educated people fled their homeland. Belleville was the center of the first important German settlement in Illinois. By 1870, an estimated 90% of the city's population was either German born or of German descent.