Island of the Gate


The King of the Island of the Gate was the father of one of Arthur’s Irish knights.

The Irish knight slept with his mother and sister, slew his father, murdered the rest of his family, and then fell burning from a tower at Camelot. His suicide was one of the marvels surrounding Galahad’s arrival at court.


Source
Post-Vulgate Queste del Saint Graal | 1230-1240