O'Brien - Irish Surname Origin & Meaning

Irish form: Ó Briain

Meaning: descendant of Brian (Boru) - “noble, high”

Traditional stronghold: Clare, Limerick, Tipperary

Pronunciation: oh-BRY-en; Irish O Briain: oh BREE-in

History of the O'Brien name

The O'Briens descend from Brian Boru, High King of Ireland, and take their name from him directly. As the ruling family of the Dal gCais, they held the kingship of Thomond, centred on Clare and north Munster, for centuries, and later became Earls of Thomond and Viscounts Clare under the Crown while retaining vast estates. Because of this royal descent the name carried exceptional prestige, and O'Brien septs and their followers spread the surname well beyond Clare into Limerick and Tipperary. It remains one of the most numerous Irish surnames and is strongly associated with Munster identity and history.

Variants: O'Brian · Bryan · Brien

Famous bearers of the name

  • Edna O'Brien - Clare-born novelist, author of The Country Girls trilogy
  • Conor Cruise O'Brien - Irish diplomat, politician and writer
  • Vincent O'Brien - Legendary Irish racehorse trainer
  • Flann O'Brien - Pen name of Brian O'Nolan, novelist of At Swim-Two-Birds

Related names from the same part of Ireland: Ryan · Kennedy · Quinn · Collins · Fitzgerald · McDonnell · McMahon · Carroll

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