Its source is an Ancient Celtic expression meaning "Exalted and high-minded."
This name is associated, in history and legend, with Brian Boru, high king of Ireland in the 10th century.
Brian united his island nation, giving the people a welcome respite from warfare. For a time, arts and culture flourished.
Of course, there were those who resented Brian and his power. Among these were the Danes, one of the groups Brian suppressed in his fight for the throne. In league with other disgruntled factions, they attempted to depose him.
Brian's forces triumphed at the Battle of Clontarf, driving the Danes out for good, but it was a Pyrrhic victory. Not only were Brian's son and grandson cut down, but Brian Boru himself was numbered among the slain.