John Butler, 12th Baron Dunboyne was an Irish clergyman and aristocrat, Roman Catholic Bishop of Cork and Ross. In order to advance his temporal title and marry he became, as of 2004, the only authenticated apostate in the Catholic hierarchy in Ireland
- Occupation
- Catholic priest, Catholic deacon, Catholic bishop
- Position held
- Roman Catholic Bishop of Cork
- Born
- 1731
- Died
- May 7, 1800, May 8, 1800
