Brian Boru had established the high-kingship of Ireland as a fact. Where other provincial kings had striven for overlordship with only partial success, he, ‘a stranger in sovereignty’, had seized the mastery. 1 But his overlordship was personal, and after the Batde of Clontarf leadership was resumed by Máel-Sechnaill II of Meath until his death in 1022. In Munster, Donnchad son of Brian ruled until 1063 (A.I.), but failed to hold the position which his father had won in the Southern’ Half and was defeated by his nephew Toirdelbach (Turlough) Ua Briain, who became the most powerful king in Ireland, securing the submission not only of Munster but of Connacht, Meath, and Breifne, and appointing his son Muirchertach as king of Dublin. Toirdelbach’s death in 1086 was followed by a period when leadership was disputed between his son Muirchertach king of Munster and Domnall Mac Loch-lainn king of Ailech. When these two died in 1119 and 1121, the rising star was the king of Connacht, Toirdelbach Ua Conchobair.