Gwynedd (fictional)
The fictional Kingdom of Gwynedd is the primary setting of the Deryni series of historical fantasy novels by Katherine Kurtz.
There had been a historical Kingdom of Gwynedd, an important part of Wales with a long history of its own. The fictional kingdom is in no way identical to it; still, it was clearly the writer's conscious decision to use the name of an actual kingdom, rather than invent a fictional name.
Read more about Gwynedd (fictional): Geography, Government, Heraldry, Religion, Kings of Gwynedd, Sources