[4] In 1790, Theodore Brouwers purchased land near present-day Latrobe to create the first parish in Pennsylvania west of the Allegheny Mountains.

[6] As the Catholic population grew in Pennsylvania in the 19th century, the Vatican erected the Diocese of Pittsburgh in 1843 to cover the western part of the state.

[8] Lamb helped found Jeannette District Memorial Hospital in Greensburg, donating over $300,000 for its construction and securing the Sisters of Charity of Seton Hill to staff it.

[12] He said his greatest accomplishment was the renovation of Blessed Sacrament Cathedral in 1972 to accommodate the liturgical reforms from the Second Vatican Council.

His replacement was Auxiliary Bishop Anthony G. Bosco of Pittsburgh, named by Pope John Paul II in 1987.

[19][20] Norbert F. Gaughan (1975–1984), appointed Bishop of Gary As of 2017, there are 78 parishes within the Diocese of Greensburg; 38 of them are in a partnered configuration.

[25] In April 1955, the diocese started receiving reports that Raymond Lukac was fraternizing with teenage girls in his parish.

In 1984, the diocese gave Sinclair a good recommendation to join the US Air Force Chaplain Corps.

[29] According to The Philadelphia Inquirer, in 2017 the Dioceses of Harrisburg and Greensburg attempted to shut down the grand jury investigation.

[30][31] In July 2018, John T. Sweeney, a diocesan priest, pleaded guilty to molesting a fourth grade boy between September 1991 and June 1992.

"[33] The diocese also agreed to report any alleged incident of sexual abuse to the "PA Childline and the appropriate district attorney.

[38] In October 2019, Bishop Brandt and the diocese were sued by a woman who had alleged that she had been raped beginning at age 12 by George Pierce in 1972.

In 2004, Brandt had sent a request to Cardinal Josef Ratzinger, head of the Congregation for the Doctrine of the Faith in Rome, to laicize Pierce.

Town officials passed news of the incident that same week to the diocese, along with complaints from other residents about Sredzinski's relationships with boys.

The second lawsuit claimed that Leonard Bealko molested a 12-year-old altar boy more than 200 times over four years, ending in 1978, at Transfiguration Church in Mt.

[42] Also in August 2020, police arrested Andrew Kawecki for sexually abusing an altar boy on multiple occasions from 2004 to 2007, beginning when the alleged victim was 11.

That same day in August 2020, Malesic announced that the diocese found credible sexual abuse allegations against Emil Payer.

The passing of the statute of limitations prevented authorities from filing criminal sexual abuse charges against Payer.

[45] In November 2020, the Pennsylvania Supreme Court denied a petition filed by the diocese to grant a stay which would have delayed an ongoing lawsuit against it.