Ruaidhrí mac Raghnaill was a leading figure in the Kingdom of the Isles and a member of Clann Somhairle. He was a son of Raghnall mac Somhairle and was the eponymous ancestor of Clann Ruaidhrí. Ruaidhrí may have become the principal member of Clann Somhairle following the annihilation of Aonghus mac Somhairle in 1210. At about this time, Ruaidhrí seems to have overseen a marital alliance with the reigning representative of the Crovan dynasty, Rǫgnvaldr Guðrøðarson, King of the Isles, and to have contributed to a reunification of the Kingdom of the Isles between Clann Somhairle and the Crovan dynasty.

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Ruaidhrí mac Raghnaill was a leading figure in the Kingdom of the Isles and a member of Clann Somhairle. He was a son of Raghnall mac Somhairle and was the eponymous ancestor of Clann Ruaidhrí. Ruaidhrí may have become the principal member of Clann Somhairle following the annihilation of Aonghus mac Somhairle in 1210. At about this time, Ruaidhrí seems to have overseen a marital alliance with the reigning representative of the Crovan dynasty, Rǫgnvaldr Guðrøðarson, King of the Isles, and to have contributed to a reunification of the Kingdom of the Isles between Clann Somhairle and the Crovan dynasty.