Saint Cadoc or Cadog, Abbot of Llancarfan, was one of the 6th century Welsh saints whose life touched King Arthur. The Abbey of Llancarfan, near Cowbridge in Glamorganshire, which he founded circa 518, became famous as a centre of learning. The prefix of his name means 'battle'. Cadoc's story appears in the "Buchedd Cadog" (or 'Life of Cadoc') written by Lifris of Llancarfan in circa 1100. Wikipedia