Duchies of Gwynedd (fictional)

The Duchies of Gwynedd are the largest feudal estates within the fictional Kingdom of Gwynedd in the Deryni novels of Katherine Kurtz. Each duchy is governed by a hereditary noble (a duke or duchess) who rules their land in exchange for swearing fealty to the Crown. Dukes are the most powerful nobles in the kingdom, wielding the power of high and low justice, and their authority in secular matters is surpassed only by the Crown. While dukes and duchesses enjoy the prestige and income of being in the ruling class of Gwyneddan society, they are required to pay appropriate taxes for their lands, see to the defense of their borders, and uphold the laws of the kingdom.

The Duchy of Carthmoor is located in the far southern Gwynedd, bordered to the north by the Royal Duchy of Haldane and to the west by the Kingdom of Llannedd. The lands of Carthmoor are originally part of the Kingdom of Mooryn, but they are incorporated into Gwynedd following Mooryn's dissolution in the ninth century. The first Dukes of Carthmoor are members of the House of Festil, and they are permitted to retain the title after the Haldane Restoration by King Cinhil I Haldane because they have no legal rights to the Festillic claim to the throne. However, they are eventually forced out by the Regents of King Alroy Haldane in 917, and the title is later granted to Alroy's youngest brother, Prince Rhys Michael Haldane. Over the years, the duchy becomes the traditional title of the second sons of the Kings of Gwynedd, but it has also served as a secondary title for the king when there is no Haldane male to hold the office. In 1130, the eleventh Duke of Carthmoor is Prince Nigel Haldane, the second son of King Donal Blaine Haldane and the uncle of King Kelson Haldane.

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