Note:  Do not rely on this information. It is very old.

Brian

Brian, surnamed Boru or Boroihme, i.e. the conqueror who makes them pay tribute, an Irish king, who may be called the King Alfred of Ireland, both as to his conquests and his efforts for the improvement of his people. He succeeded in 976 his brother, who was a petty kinglet. He made himself king of Cashel by his sword, and also made his rule felt in Munster, and in 984 was acknowledged king of Leinster. He established his chief seat of government at Killaloe, and had establishments at Tara and at Cashel. He allied himself with the Danes, and by their aid became King of Ireland. In this latter capacity he founded universities and made efforts in all directions for the well-being of his people. In his old age he gave the Danes a crushing defeat at the battle of Clontarf, but paid for the victory with his life. King Brian is said to have introduced the patronymic prefixes "Mac" and "O," the former to denote "the son of" and the latter to denote "the grandson or further descendant of."

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