The Diocese of Belleville () is a Latin Church ecclesiastical territory or diocese of the Catholic Church in the southern Illinois region of the United States. It comprises the southern counties of the state of Illinois and the See city for the diocese is the City of Belleville. It is a suffragan see in the ecclesiastical province of the metropolitan Archdiocese of Chicago. The cathedral parish for the diocese is the Cathedral of Saint Peter. Following the resignation of Edward Braxton on April 3, 2020, Michael G. McGovern was installed as the current Bishop of Belleville. History Early history During the 17th century, present day Illinois was part of the French colony of New France. The Diocese of Quebec, which had jurisdiction over the colony, sent numerous French missionaries to the region. Reverend Claude-Jean Allouez was stationed at Kaskaskia, Illinois, for eight weeks from early June to the middles of August 1673, before returning to St. Francis Xavier Mission near Green Bay, Wisconsin. Illinois has some of the oldest catholic churches in the American Midwest. The records of the church of Kaskaskia, dating back to 1695, name Reverend Jacques Gravier as the missionary priest. French missionaries opened the Cahokia mission of Holy Family in 1699. At that time, the Catholics of Cahokia and the surrounding territory, including the city of St. Louis across the river, were attended to by Father De Saintpierre. The organization of the congregation of Prairie du Rocher, Illinois coincides with the building of the first Fort de Chartres on the Mississippi River in 1720. Reverend Jen Le Boullenger, chaplain of the militia stationed at the Fort, was placed in charge of the congregation. The mission church was dedicated to St. Anne. In 1743, the Rev. J. Gagnon took charge of the mission, serving there until his death in 1755. His remains were interred alongside the altar in the chapel in the mission cemetery. This chapel was built in 1734, and dedicated to St. Joseph. In 1768, Reverend Pierre Gibault was appointed vicar general of the Archdiocese of Quebec for the Illinois area, now part of the British Province of Quebec. In 1776. the Illinois area was claimed by the new United States. In 1785, Archbishop John Carroll sent his first missionary to Illinois, which became part of the Northwest Territory in 1787. With the creation of the Diocese of Bardstown in Kentucky in 1810, supervision of