Derry
The Earldom of Derry stretches along the western side of the Coamer Mountains in eastern Gwynedd, extending north of the Lendour Mountains. The earldom is created by King Uthyr Haldane in 953, and bestowed upon Lord Flynn Fitz-Arthur-Quinnell, the second son of the first Duke of Cassan, in recognition of his service to the Crown of Gwynedd. The earl's descendants later adopt the surname O'Flynn in his honor, and the family holds the title without interruption into the twelfth century. The ninth Earl of Derry, Earl Sean O'Flynn, is appointed to the Royal Council of King Kelson Haldane in 1120.
Read more about this topic: Earldoms Of Gwynedd (fictional)