Dermot MacMurrough (c. 1110 – c. 1 May 1171), was King of Leinster in Ireland from 1127 to 1171. In 1167, he was deposed by the High King of Ireland, Ruaidrí Ua Conchobair. To recover his kingdom, MacMurrough solicited help from King Henry II of England. His issue unresolved, he gained the military support of the Richard De Clare, 2nd Earl of Pembroke (otherwise known as "Strongbow"), thus initiating the Anglo-Norman invasion of Ireland.