Dictionary of National Biography, 1885-1900/Rhys ab Owain
RHYS ab OWAIN (d. 1078), Welsh prince, was the son of Owain ab Edwin ab Einon ab Owain ap Hywel Dda. He was one of the leaders defeated by William FitzOsbern [q. v.] in an expedition led by the latter about 1070 against the people of Brecknock (Ord. Vit. iv. 7). On the death of his brother Maredudd in 1071, Bleddyn ap Cynfyn of North Wales appears to have seized the crown of Deheubarth, but in 1075 Rhys and the headmen of Ystrad Tywi (East Carmarthenshire) slew the northern prince, and South Wales was divided between Rhys and Rhydderch ap Caradog, who in the same year defeated Gronw and Llywelyn, sons of Cadwgan, in the battle of Camddwr. In 1076 the death of Rhydderch left Rhys in sole possession; he defeated the sons of Cadwgan once again in the following year, in the battle of ‘Guinnitul.’ In 1078 Rhys was attacked by Trahaearn ap Caradog, then ruling over North Wales; his household troops were cut to pieces, and he himself became a fugitive, disasters which were regarded in the north as a judgment for the murder of Bleddyn. Towards the end of the year he and his brother Hywel were slain by Caradog ap Gruffydd, lord of Gwynllwg (Wentloog).
[Annales Cambriæ; Bruts in Myvyrian Archaiology, 2nd edit.; Freeman's Norman Conquest, iv. 503.]