This was an O'Keeffe stronghold, one of many fortifications that this powerful Gaelic family controlled throughout County Cork. The castle served as part of their territorial network until the upheavals of the mid-17th century, when it was forfeited during the Cromwellian conquest of Ireland around the 1650s.

The absence of Drominagh Castle from the Down Survey barony maps of 1655-6 suggests that by the time William Petty's surveyors were documenting Irish lands for redistribution, the castle may have already been abandoned or destroyed. This was a common fate for many Irish castles during this turbulent period, when the old Gaelic and Old English landholding system was systematically dismantled and replaced with new Protestant settlers.

Today, visitors to Drominagh South will find only the natural rock formation that once supported this medieval fortress. The site serves as a quiet reminder of the O'Keeffe family's former influence in North Cork, and of the dramatic changes that swept through the Irish countryside during the 17th century. Archaeological records from the late 20th century confirm the historical accounts of the castle's existence, even though the stones themselves have long since vanished into history.