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.

Pope Pius VII on June 19, 1821, erected the Diocese of Cincinnati, taking all of Ohio from Bardstown.

[5] Pope Pius IX erected the Diocese of Cleveland on April 23, 1847, with territory taken from the Archdiocese of Cincinnati.

At that point, the diocese included counties going west to Toledo and south to Youngstown He named Reverend Louis Rappe as the first bishop of Cleveland.

In 1872, Pope Pius IX appointed Reverend Richard Gilmour of the Archdiocese of Cincinnati as the second bishop of Cleveland.

[13] He established St. Ann's Asylum and Maternity Home,[14] St. Michael Hospital,[15] and St. John Hospital.In 1882, Gilmour condemned the Ladies Land League chapter in Cleveland..

[16] After Gimour died in 1891, Pope Leo XIII named Reverend Ignatius Horstmann of the Archdiocese of Philadelphia as the new bishop of Cleveland.

Despite Horstmann's refusal, Kolaszewski continued to press for independence and accused the bishop of sexual abuse crimes.

In 1894, a group of parishioners started a new independent parish, Immaculate Heart of Mary, with Kolaszewski as pastor; Horstmann excommunicated all of them.

After removing Reverend Kasimir Zakrajsek as pastor of St. Vitus Parish in Cleveland, he faced violent protests.

On September 22, 1907, 5,000 Polish protesters marched on Horstmann's residence, demanding Zakrajsek's reinstatement and home rule for St.

Pope Pius IX named Reverend John Farrelly of the Diocese of Nashville as bishop of Cleveland in 1909.

Christine, a 13-year-old girl who died for her Catholic faith around 300 AD, was moved from the Roman catacombs to St. John's Cathedral in Cleveland.

[28] Hoban opened a minor seminary and expanded the Newman Apostolate for Catholic students attending public universities and colleges.

As bishop, Issenmann constructed the following schools in the diocese: In November 1968, Issenmann asked all adults attending mass in the diocese to sign petitions of support for Humanae vitae, Pope Paul VI's 1969 encyclical against artificial birth control.

In 2005, 36 lay members of the diocese sued Pilla, accusing him of allowing $2 million in diocesan funds to be stolen.

In 2004, Phila received an anonymous letter accusing Joseph Smith, the assistant treasurer for the diocese, of theft.

In August 2007 Smith and Anton Zgoznik, a hired consultant, were charged with 17 counts of money laundering and tax evasion.

Pope Francis in 2017 appointed Auxiliary Bishop Nelson J. Perez of the Diocese of Rockville Centre to replace Lennon.

Earlier that year, Cuyahoga County Prosecutor William Mason announced an investigation of sexual abuse of minors by diocesan priests.

[39] In July 2011, an Ohio man sued Pilla and the diocese, saying that their negligence allowed a priest to sexually abuse him when he was a boy.

[42] In December 2019, Reverend Robert McWilliams, a diocesan priest, was arrested at St. Joseph Parish in Strongsville on four counts of possessing child pornography.

"[44] McWilliams pleaded guilty in July 2021 to sex trafficking of youths, sexual exploitation of children and possession of child pornography.

[46] In March 2023, four women sued the diocese, saying that they had been sexually and physically assaulted at the Parmadale Children's Village in Parma.

[48] He had been indicted in November 2023 on six counts of gross sexual imposition, being accused of inappropriately touching a 15-year-old girl with cancer while performing a "blessing" in Westlake in October 2023.

[48] Despite being able to perform the blessing by this time, it is believed that Barajas had previously been removed from priesthood soon after he was accused in 1989 of sexually abusing juveniles in the Diocese of Harrisburg.