[1][2] On 29 June 2020, it was announced that Pope Francis had appointed Martin Hayes, a former priest of the Archdiocese of Cashel and Emly, as Bishop of Kilmore in succession to Philip Leo O'Reilly.

The diocese of Kilmore was originally called Breifne (Latin: Tirbrunensis, Tybruinensis or Triburnia; Irish: Tír mBriúin, meaning "the land of the descendants of Brian", one of the Uí Briúin kings of Connacht).

It was rebuilt and became known in Irish as An Chill Mhór (meaning Great Church) and anglicised as Kilmore, which gave its name to the diocese, a name which has remained ever since.

After a period of two hundred years of uncertainty, Bishop Denis Maguire (1770–98) gave new stability to the diocese and started the process of rebuilding both discipline and churches.

[7] The Kilmore Diocesan Pastoral Centre was created in 2005, in the old boarding school wing of St. Patrick's College, Cavan.