Brian Boru. Brian Boru (c. 941 – 23 April 1014, Old Irish: Brian Bóruma mac Cennétig; Middle Irish: Brian Bóruma; modern Irish: Brian Bóroimhe) was an Irish king who ended the domination of the High Kingship of Ireland by the Uí Néill.
Building on the achievements of his father, Cennétig mac Lorcain, and especially his elder brother, Mathgamain, Brian first made himself King of Munster, then subjugated Leinster, eventually becoming King of All Ireland. He is the founder of the O'Brien dynasty. Brian Boru. The line between Irish Legend and Irish Myth has often been blurred, especially as the retelling of heroic deeds has been passed on through generations. Brian Boru was no legend although his life deeds were legendary. He was very much a real man and was in fact the last great High King of Ireland and perhaps the greatest military leader the country has ever known. Brian Boru was born Brian Mac Cennétig. Charlemagne.