Amhar

King Arthur's family grew throughout the centuries with King Arthur's legend. Several of the legendary members of this mythical king's family became leading characters of mythical tales in their own right.

In Welsh Arthurian literature from before the time of Geoffrey of Monmouth's Historia Regum Britanniae (History of the Kings of Britain), Arthur was granted numerous relations and family members. Several early Welsh sources are usually taken as indicative of Uther Pendragon being known as Arthur's father before Geoffrey wrote, with Arthur also being granted a brother (Madog) and a nephew (Eliwlod) in these texts. Arthur also appears to have been assigned a sister in this material – Gwalchmei is named as his sister-son (nephew) in Culhwch and Olwen, his mother being one Gwyar.Rachel Bromwich and D. Simon Evans have observed that Culhwch and Olwen, the Vita Iltuti and the Brut Dingestow combine to suggest that Arthur had a mother too, named Eigyr.

In addition to this immediate family, Arthur was said to have had a great variety of more distant relatives, including maternal aunts, uncles, cousins and a grandfather named Anlawd (or Amlawdd) Wledig ("Prince Anlawd"). The latter is the common link between many of these figures and Arthur: thus the relationship of first cousins that is implied or stated between Arthur, Culhwch, Illtud, and Goreu mab Custenhin depends upon all of their mothers being daughters of this Anlawd, who appears to be ultimately a genealogical construct designed to allow such inter-relationships between characters to be postulated by medieval Welsh authors. Arthur's maternal uncles in Culhwch and Olwen, including Llygatrud Emys, Gwrbothu Hen, Gweir Gwrhyt Ennwir and Gweir Baladir Hir, similarly appear to derive from this relationship.

The genealogies from the thirteenth century Mostyn MS. 117 assert that Arthur is the son of Uthyr, the son of Custennin, the son of Cynfawr, the son of Tudwal, the son of Morfawr, the son of Eudaf, the son of Cadwr the son of Cynan, the son of Caradoc, the son of Bran, the son of Llŷr.

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