Dictionary of National Biography, 1885-1900/Llywarch ab Llywelyn
LLYWARCH ab LLYWELYN, otherwise known as Prydydd y Moch (fl. 1160–1220), Welsh bard, was author of many poems, chiefly addressed to chieftains of North Wales, including David and Rhodri, sons of Owain Gwynedd, who divided the sovereignty between them about 1170, and Llywelyn ab Iorwerth [q. v.], to whom nine pieces were inscribed. All contain valuable historical material. Thirty-two of his poems have been printed in the 'Myvyrian Archaiology of Wales,' pp. 199-217; one of these is an invocation when undergoing the fiery ordeal to exonerate himself from having any knowledge of the fate of Madog (fl. 1172) [q. v.], the son of Owain Gwynedd, who it was subsequently alleged had sailed for America, which he had discovered in 1170. Llywarch possessed more poetic genius than any of his contemporaries, and has been justly described as the most illustrious Welsh bard of the middle ages. Some of Llywarch's manuscripts are in the Hengwrt collection, others are at Mostyn, and a few poems are included in the 'Red Book of Hergest' at Jesus College, Oxford (Edward Lluyd, Archæologia, pp. 259, 261).
[Owen's Cambr. Biography; Williams's Eminent Welshmen, s.v.]