Beli Mawr was an ancestor figure in medieval Welsh literature and genealogies. He is the father of Caswallawn, Arianrhod, Lludd Llaw Eraint, Llefelys, and Afallach. Other sources give his wife as Dôn, daughter of Mathonwy. 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–are not mentioned in the medieval Welsh literature. Several royal lines in medieval Wales traced their ancestry to Beli. Celi Mawr is considered to be the lord of the Sun, the burning man and the father light.