Ceidiaw Galloway and Kyle (?), fl 540s-550s.
Ceidiaw (or Keidyaw) is remembered only as the father of Gwenddolau. We may presume that he helped conquer the lands around Galloway and Kyle, and possibly into northern Rheged sometime in the middle of sixth century. He may have usurped the kingdom of Rhun. It is interesting to speculate whether he was the origin of either Geoffrey of Monmouth’s Cador of Cornwall or of the legendary Arthur’s seneschal Cei or Kay.540