He is listed in two paternal pedigrees found in Bonedd yr arwr as the direct descendant of Arthur, though the genealogies themselves differ quite markedly. However, when studied more closely, it becomes obvious that the pedigree that appears first in the work has skipped three generations.
Another interesting paternal pedigree for Arthur, which names his descent as direct from Llyr, is to be found in the Mostyn MS 117. When the three lines of descent are compared, it is not hard to see that all three are obviously based on the same source material.
An ancestor of Arthur, both paternal and maternal, who occurs in Welsh pedigrees. In origin he may have been a divinity of the sea (Welsh: llyr = sea) who was regarded as the ancestor of a number of royal houses.
Most sources makes him the father of Caradoc Briefbras (Caradoc Vreichvras). He would seem to be the original of Shakespeare's King Lear, though this character is normally associated with Leir, he may have originated from Llyr.