Dictionary of National Biography, 1885-1900/Moelmud, Dyfnwal
MOELMUD, DYFNWAL (fl. 500), Northern British prince, appears in the tenth-century genealogies of Harleian MS. 3859 (Cymmrodor, ix. 174) as a grandson of Coel Odebog. This is the sole reference to him which can be called historical. In later Welsh literature he plays a purely mythical part. He becomes the primitive legislator of the Britons, the deviser of all early British institutions. In this capacity he appears in the narrative of Geoffrey of Monmouth, who makes him the son of Cloten, king of Cornwall, and says that the laws drawn up by him were still in use among the English. Geoffrey's account is accepted by the compiler of the 'Venedotian Code,' who flourished about 1220; according to this writer, Hywel the Good, while altering greatly the old laws of Dyfnwal, left untouched the primitive land measurements (Ancient Laws of Wales, 1841 edit. i. 184). Dyfnwal is not mentioned in the two earlier sets of 'Historical Triads,' but is prominent in the third, having a place assigned him among the Columns, the Mighty Binders, the Primitive Instructors, and the Benign Monarchs of the isle of Britain (Myvyrian Archaiology, 2nd edition, pp. 400, 404, 406, 407). About the time when this series of ' Triads ' was composed, viz., in the sixteenth century, the legislator's fame stood so high as to induce a Welsh antiquary to give the name 'The Triads of Dyfnwal Moelmud' to the collection of legal maxims in which he had embodied his views as to ideal social relations in Wales. These 'Triads' form book xiii. in Mr. Aneurin Owen's edition of the Welshlaws. Attempts have been made to show that they contain remnants of ancient tradition (e.g. by Peter Roberts in an appendix to his translation of the 'Chronicle of the Kings of Britain,' 1811), but they are beyond doubt modern in form and substance. Professor Rhys treats even Dyfnwal himself as an entirely mythical person, classing him with the dark or Chthonian divinities of the Celtic pantheon (Celtic Heathendom, p. 449; Arthurian Legend, pp. 261, 394).
[Genealogies in Harleian MS. 3859; Ancient Welsh Laws, 1841 edit.; Geoffrey of Monmouth; Historical Triads in Myvyrian Archaiology, 2nd edit.]