Somhairle Buidhe Mac Domhnaill (Somerled of the yellow hair, son of Donnell, anglicised Sorley Boy McDonnell, or MacDonald in Scotland) (c. 1505 – 1590), Scoto-Irish prince or flaith and chief, was the son of Alexander MacDonnell, lord of Islay and Kintyre (Cantire), and Catherine, daughter of the Lord of Ardnamurchan. MacDonnell is best known for establishing the MacDonnell clan in Antrim and resisting the campaign of Shane O'Neill and the English crown to expel the clan from Ireland.