The Diocese of Belleville (Latin: Diœcesis Bellevillensis) is a Latin Church ecclesiastical territory, or diocese, of the Catholic Church in the Southern Illinois region of the United States. It is a suffragan see in the ecclesiastical province of the metropolitan Archdiocese of Chicago.

The mother church for the diocese is the Cathedral of Saint Peter in Belleville. Michael G. McGovern is the current bishop of Belleville.

During the 17th century, the Illinois Country 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. It was estimated that 15,000 to 20,000 Native American converts and French trappers and settlers throughout the region were tended to by these Jesuit missionaries.

The French missionary Claude-Jean Allouez was stationed at Kaskaskia, Illinois, for eight weeks from June to August 1673 before returning to St. Francis Xavier Mission near De Pere, 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 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. Jen Le Boullenger, chaplain of the militia stationed at the Fort, was placed in charge of the congregation. The mission church was dedicated to Saint Anne. In 1743, 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 Saint Joseph. In 1768, 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. After the American Revolution ended in 1783, Pope Pius VI erected in 1784 the Prefecture Apostolic of the United States, encompassing the entire territory of the new nation. In 1785, the vicar apostolic, John Carroll, sent his first missionary to Illinois. In 1787, the Illinois area became part of the Northwest Territory of the United States. Pius VI created the Diocese of Baltimore, the first diocese in the United States, to replace the prefecture apostolic in 1789.

When the Vatican erected the Diocese of Bardstown in Kentucky in 1808, it gained jurisdiction over the Illinois area. The earliest parishes in the region were the Irish St. Patrick's in Ruma in 1818, the French St. Francis in St. Francisville in 1818 and the English St. Augustine of Canterbury in Hecker in 1824. In 1827, the Diocese of St. Louis assumed jurisdiction over the western half of the new state of Illinois. In 1834, the Vatican erected the Diocese of Vincennes, which included eastern Illinois.

When the Diocese of Chicago was erected in 1843, it included all the Illinois counties from the Diocese of St. Louis and Vincennes. In 1857, Pope Pius IX erected the new Diocese of Alton, transferring all of Southern Illinois from the Diocese of Chicago. The Southern Illinois area would remain part of the Diocese of Alton, for the next 30 years.

The Diocese of Belleville was created on January 7, 1887, by Pope Leo XIII. All of its in southern Illinois territory was taken from the Diocese of Alton. The first bishop of the new diocese was John Janssen of Alton, appointed by the pope in 1888. By 1902, the diocese contained 104 churches, 94 priests, 64 parochial schools and 50,000 Catholics. In 1903, at Janssen's request, the Poor Handmaids of Christ religious order set up a hospital in East St. Louis, Illinois. The hospital was open to all patients, regardless of race or religion. Janssen died in 1913.

Pope Pius X appointed Henry J. Althoff as bishop of Belleville in 1913 to replace Janssen. In July 1927. Atholl banned female parishioners from receiving communion if they were wearing makeup, sleeveless tops or low-cut tops. In 1937, Althoff forbade church-sponsored gambling in the diocese, encouraging Catholics to support their parishes by direct contribution rather than parish parties and festivals. Later that year, he banned dancing the night before a holy day. Since New Years Day was a holy day, that meant no dancing on New Year's Eve.

Althoff died in 1947 after a 20-year tenure as bishop. Pope Pius XII named Albert Zuroweste as the next bishop of Belleville. In 1969, Zuroweste became embroiled in a racial dispute in Cairo, Illinois. He had sent Fr Gerald Montroy to Cairo in 1968 to minister to the poor and to African-Americans. After meeting with the local pastor at St. Patrick Catholic Church, Montroy became convinced that the pastor had no desire to welcome African-Americans to his parish. In response, Montroy reopened St. Columba, a shuttered mission in Cairo founded by the Society of African Missions, and started holding Masses there for African-American Catholics. He also provided facilities for Black Power activists looking to challenge racial discrimination in that city, including Charles Koen and his United Front organization. Zuroweste came under pressure from White Cairo residents to recall Montroy, but gave him qualified support after demands from progressive Catholic organizations. After several shooting incidents, Montroy accused a local white group of vigilantism and St. Patrick's pastor of trying to oust him.

In December 1971, Zuroweste excommunicated Bernard Bodewes, a diocesan priest he had sent to Cairo to help Montroy. Bodewes had sued Zuroweste for $7,350 in damages for withholding his pay since January 1 of that year. Bodewes said that Zuroweste had withheld the pay because he was angry over Bodewes' support of Montroy's initiatives in Cairo. By 1972, Zuroweste took action to evict Montroy and the organizations working in St. Columba.

When Zuroweste retired in 1977, Pope Paul VI named Auxiliary Bishop William Cosgrove of the Diocese of Cleveland. as the next bishop of Belleville. Cosgrove served until his retirement in 1981. Pope John Paul II replaced Zuroweste that same year with John Wurm from the Archdiocese of St. Louis. Wurm died three years later. John Paul II then appointed James Patrick Keleher of the Archdiocese of Chicago as the new bishop of Belleville. In 1993, the pope named Keleher archbishop of Kansas City in Kansas. Auxiliary Bishop Wilton Gregory of the Archdiocese of Chicago was appointed by John Paul II as bishop of the Diocese of Belleville in 1993. In 2004, the pope named him as archbishop of the Archdiocese of Atlanta.

John Paul II appointed Edward K. Braxton as bishop in 2005. Braxton retired in 2020.

The current bishop of Belleville is Michael G. McGovern from the Archdiocese of Chicago, appointed by Pope Francis in 2020. In July 2022, McGovern announced the planned sale of the diocesan bishop's residence and his move to a more modest space in the Cathedral of St. Peter rectory. The money from the sale, he announced, would be used to subsidize various ministries and charities, including the establishment of a fund benefiting expectant mothers and children.

During the course of 1993, Bishop Keleher removed seven priests and one deacon with credible accusations of sexual abuse of minors from ministry in the diocese.

A 2008 lawsuit against the Diocese of Belleville revealed Bishop Zuroweste's treatment of a sexual abuse allegations against a priest during the 1970's. In 1973, Gina Parks, a 16-year-old parishioner in St. Francisville, told diocesan officials that her parish priest, Raymond Kownacki, had raped and impregnated her. After learning of her pregnancy, Kownacki encouraged Parks to have an abortion. After hearing her story, Zuroweste transferred Kownacki to St. Theresa Parish in Salem without any restrictions. By 1982, allegations surfaced that Kownacki was sexually abusing young boys at St. Theresa, in particular 12 year old James Wisniewski. In 2002, Wisniewski sued the diocese. In 2008, he was awarded $2.4 million in compensatory damages and an unexpected $2.6 million in punitive damages. The Vatican laicized Kownacki in 2011.

An Illinois man known as J. Christ sued the diocese for $100,000 in 2014, saying that he was sexually abused in the summers of 1970 and 1971 by Robert J. Vonnahmen at Camp Ondessonk in Ozark. The plaintiff said that Vonnahmen fondled and raped him on many occasions. Removed from ministry in 1993, Vonnahmen was laicized by the Vatican in 2008.

In 2019, the diocese was sued by a man who claimed that Joseph Schwaegel, a senior official in the diocese, had sexually abused him in 1987. The diocese in 1999 had settled a similar case against Schwaegel, who they removed from ministry in 1994. At the time of his removal, Schwaegel admitted that he was a "sex addict'', but denied abusing children.

In October 2020, Bishop McGovern removed Anthony Onyango from his position as administrator for two parishes, citing an allegation of verbal misconduct with a minor. Onyango was laicized in 2022 by the Vatican.

On May 23, 2023, the Illinois Attorney General released a report on Catholic clergy child sex abuse in Illinois. The multi-year investigation found that more than 450 Catholic clergy in Illinois abused nearly 2,000 children since 1950.

1. John Janssen (1888–1913)
2. Henry J. Althoff (1913–1947)
3. Albert Rudolph Zuroweste (1947–1976)
4. William Michael Cosgrove (1976–1981)
5. John Nicholas Wurm (1981–1984)
6. James Patrick Keleher (1984–1993), appointed Archbishop of Kansas City in Kansas
7. Wilton Daniel Gregory (1993–2004), appointed Archbishop of Atlanta
8. Edward Kenneth Braxton (2005–2020)
9. Michael McGovern (2020–Present)

Stanley Girard Schlarman (1979-1983), appointed Bishop of Dodge City

Joseph Henry Leo Schlarman, appointed Bishop of Peoria in 1930 and subsequently named archbishop ad personam

• Althoff Catholic High School – Belleville
• Gibault Catholic High School – Waterloo
• Mater Dei High School – Breese

• Camp Ondessonk – Ozark

• Pierre-Gabriel Marest, missionary at Kaskaskia

Media related to Roman Catholic Diocese of Belleville at Wikimedia Commons

• Roman Catholic Diocese of Belleville Official Site

38°31′18″N 89°59′43″W / 38.52167°N 89.99528°W / 38.52167; -89.99528