The establishment of a Diocese of Dromore, comparable to what we have today, was a consequence of the reordering of the Irish Church by Rome in the twelfth century. The area that formed the small diocese coincided with the medieval baronies or territories of Upper and Lower Iveagh, what we might term today south and west Co Down. It also included a portion of O’Neill land, that part of Co Armagh which lies east of the river Bann, and a tiny piece of south-west Co Antrim.
