Beli Mawr

Beli Mawr ("Beli the Great") was an ancestor figure in Middle Welsh literature and genealogies. He is the father of Cassivellaunus, Arianrhod, Lludd Llaw Eraint, Llefelys, and Afallach. In certain medieval genealogies he is listed as the husband of Anna, cousin of Mary, mother of Jesus. According to the Welsh Triads, Beli and Dôn were the parents of Arianrhod, but the mother of Beli's other children—and the father of Dôn's other children—is not mentioned in the medieval Welsh literature. Several royal lines in medieval Wales traced their ancestry to Beli. The Mabinogi names Penarddun as a daughter of Beli Mawr, but the genealogy is confused; it is possible she was meant to be his sister rather than daughter.

The origin of the name Beli is still a matter of debate among scholars. The most popular hypothesis sees the name Beli as a Middle Welsh reflex of the Gaulish and Brittonic divine name Belenus (also attested as a personal name), but a more recent alternative is that proposed by the Celticist John T. Koch, who suggests that Beli derives from a Proto-Celtic name Belgius or Bolgios borne by one of the chieftains who led the Gallic invasion of Macedonia in 280–279 BCE. He therefore proposes that this great leader Belgius came to be regarded as the namesake and ancestor of the powerful Brittonic and Gallic tribal group, the Belgae, whence would have come the doctrine that Beli was the ancestor of tribal dynasties.

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