B. c.1162, 4th s. of Rhys ap Gruffydd and Gwenllian; acc. 1204; m. Joan, da. of Richard, earl of Hertford; issue: Rhys, Maredudd; d. 1234; bur. St David's cathedral.
Rhys usually acted with his eldest brother Gruffydd against their volatile younger brother, Maelgwyn. On Gruffydd's early death, he took control of cantref Mawr. At first he supported king John, but in 1211 changed sides, joined Llywelyn ab Iorwerth, and stormed the royal castle at Aberystwyth. John retaliated by supporting Rhys's nephews, Rhys and Owain (sons of Gruffydd), against him, and an expedition from Brecon moved into Rhys's heartland, defeating him near Llandeilo. Rhys was captured and imprisoned at Carmarthen. He was not released until 1215 and promptly threw in his lot with Llywelyn, who restored him to cantref Mawr and cantref Bychan to the west; Deheubarth was divided up. He took part in Llywelyn's revolt of 1231, seizing the castle at Cardigan, and was still campaigning in 1234, when he was mortally wounded besieging Carmarthen.
Subjects: British History.