Brian Ruadh Ó Briain

Brian Ruadh Ó Briain (died 1277), a younger son of Conor na Siudane, succeeded his father as King of Thomond in 1268. In 1270 he attacked the Anglo-Norman colonists and stormed Clare Castle. In 1275 his nephew Toirdhealbhach drove him from Clonroad, and Brian allied himself with Thomas de Clare, to whom the English crown had granted all Thomond.

Defeated by Toirdhealbhach in 1277, he was hanged by de Clare at Bunratty. His sons Donnchadh and Domnall carried on his Clann Briain line.