由来と歴史

Anglicisation of the Irish Gaelic 'O Briain', meaning 'descendant of Brian', where Brian is thought to derive from the Old Celtic 'brig' (high, noble) or from a root meaning 'strength' or 'hill'. The name descends directly from Brian Boru (941–1014), the High King of Ireland who defeated the Vikings at the Battle of Clontarf in 1014 and unified Ireland under a single monarch for the first time. The O'Briens were Kings of Munster and among the most powerful dynasties in medieval Irish history, and the surname is most densely concentrated in counties Clare, Limerick, and Tipperary.