[Annales Cambriæ (Rolls Ser.); Brut y Tywysogion (Rolls Ser.); Brut y Tywysogion (Cambrian Archæological Association); Anglo-Saxon Chronicle; Florence of Worcester; Freeman's Norman Conquest, vol. ii.]
GRUFFYDD ab RHYS (d. 1137), king or prince of South Wales (Deheubarth), was brought up in Ireland, where in his childhood he had fled with his kinsfolk after the defeat and death of his father, Rhys ab Tewdwr [q. v.], at the hands of Bernard of Neufmarché in 1093. On that fatal day 'fell the kingdom of the Britons,' and nearly all Rhys's old kingdom was seized by Norman adventurers. Nest, Rhys's daughter, became the bride of Gerald of Windsor, steward of Pembroke. When Gruffydd had grown up to manhood he became weary of exile and inactivity, and about 1113 he returned to Dyved. For two years he wandered about the country. His return seems to have inspired the conquered Welsh with the hope of regaining their liberty under his rule. It was 'represented that the minds of all the Britons were with him in contempt of the royal title of King Henry,' and after two years he was 'accused to the king' (Brut y Tywysogion, p. 119). His request for a part of his father's lands was refused (Flor. Wig. ii. 69).
Gruffydd now escaped to North Wales and sought refuge with Gruffydd ab Cynan [q. v.], the king of Gwynedd. His brother Hywel, who had escaped maimed from the prison of Arnulf of Montgomery, went with him. Gruffydd ab Cynan treated them well at first, but was persuaded by Henry I to give up the fugitives. Gruffydd ab Rhys discovered his treachery, and managed to escape to the sanctuary of the church of Aberdaron in Lleyn, whence he returned to the south, where 'many foolish young men from every part joined him, being deceived by the desire of spoils or seeking to restore the British kingdom' (Brut y Tywysogion). He began a vigorous predatory warfare on the French and Flemish settlers in his father's realm. At first he was unsuccessful, but in the spring of 1116 his devastations became so great that they were recorded in the English chronicles (Flor. Wig. ii. 68). He burnt Narberth Castle, which protected the Flemish district of Dyved from Welsh assaults, and soon after attacked the castle of Llandovery in the vale of Towy, but he only succeeded in burning the outworks. Soon afterwards he failed equally at 'a castle that was near Abertawe' (Swansea). But the smaller Welsh chieftains joined the French, and one of them, Owain ab Caradog, saved the tower of Carmarthen Castle from falling into his hands. Gruffydd then destroyed a castle in Gower, and became so formidable that 'William of London for fear of him left his castle (Kidwelly) and his riches.' Gruffydd was thence invited into Ceredigion, and after defeating the Flemings at Blaenporth Hodnant, marched northwards, destroyed the castle of Ralph, the steward of Earl Gilbert, at Peithyll, and marched against Aberystwith. Owain ab Cadwgan was now inspired by Henry I to put down 'the thief Gruffydd,' but he was slain by the Flemings. This failure seems to have secured Gruffydd a position in South Wales.
The chroniclers make no further mention of Gruffydd for several years, and when he reappears he is in possession of a portion of land which the king had given him (Brut y Tywysogion, p. 153). The weak authority of the 'Gwentian Brut' (p. 106) says that in 1121 (probably 1124) he was made by Henry free lord of 'the vale of Towy, the cantrev of Penwedig in Ceredigion, the cantrevs of Caerwedros, Cantrevbychan, Caethinog, Caeo, Myves nydd, and other lands,' but that 'the king saw the boundaries were undefined, which furnished him with a pretext to complain of Gruffydd's acts.' But the statement of Giraldus Cambrensis, who was the grandson of Gruffydd's sister, is more probable that in the days of Henry I Gruffydd was only 'lord of a single cymmwd, that of Kaoc in Cantrevmawr.' This seems to be the district of Caio in the modern Carmarthenshire, among the hills dividing the valleys of the Towy and the Teivi (Itin. Kambr. in Op. vi. 34, with the editor's note). Gruffydd abated nothing of his claims, and Giraldus tells how the very wild fowl of Llangorse Lake testified that he was the rightful prince of South Wales (ib. pp. 34-5). In 1122 Gruffydd killed Gruffydd the son of Trahaiarn (Brut y Tywysogion, sub an. 1120). In 1127 Gruffydd was expelled from his modest lordship 'after he had been undeservedly accused by the French' (ib. sub an. 1124; Ann. Cambr. sub an. 1127). He again sought refuge in Ireland (Ann. Cambr.), but seems soon to have returned, and was probably lurking amidst the dense forests of Cantrevmawr, the great hiding-place of the South Welsh (Giraldus, Op. vi. 80), when the death of Henry I and the weak rule of King Stephen inspired the Welsh to make a great attempt to recover their freedom. Gruffydd was now again in close alliance with Gruffydd ab Cynan and his warlike sons, and had married Gwenllian, eldest daughter of the North Welsh king. In January 1136 a great Welsh host poured into Gower, and on 15 April Richard Fitzgislebert was slain by them. Gruffydd hurried
