 The little that is known about Rheged and its kings comes from the poems of Taliesin, who was bard to Urien, King of Catraeth and of Rheged (and possibly overlord of Elmet).It is known, from the poetic sources, that under Urien's leadership the kings of the north fought against the encroaching Angles of Bernicia and that he was betrayed by one of his own allies, Morcant Bulc, who arranged his assassination after the battle of "Ynys Metcaut" (Lindisfarne) around 585 AD.The Battle of Catraeth, fought by the British (c. 600 AD) to try to recover Catraeth after Urien's death, was a disastrous defeat for them.