Mongavlin Castle

Mongavlin Castle also known as Mongevlin Castle is a ruined castle on the west bank of the River Foyle, approx 3 km south of St Johnston, County Donegal, Ireland. It was once a stronghold of the O'Donnell's, Lords of Tyrconnell.

In the sixteenth century Mongevlin was the chief residence of Ineen Dubh, who was the daughter of James MacDonald, 6th of Dunnyveg, and mother of Red Hugh O'Donnell.
The State Paper recording her possession of the castle:
" From Cul-Mac-Tryan runs a bogg three myles in length to the side of Lough Foyle in the midst of the bog is a standing loughe called Bunaber here at Bunaber dwells O'Donnell's mother . Three miles above Cargan stands a fort called McGevyvelin upon the river of Lough Foyle O'Donnell's mother's chief house." When Ineen Dubh came to Ireland to marry Aodh mac Maghnusa Ó Domhnaill , she brought a force of 100 of the biggest men she could find in Scotland. These soldiers were her bodyguards, 80 of these were of the name Crawford. When the O’Donnell's eventually abandoned Mongavlin the Crawford's settled and married in the locality. Many of their descendants can still be found in the area to this day.

Wikipedia