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Irish surname

O'Brien: Irish Surname History & Coat of Arms

Ó Briain · 'descendant of Brian'

O'Brien, in Irish Ó Briain, means 'descendant of Brian'. Woulfe (1923) traces the family to Brian Boru, King of Ireland, slain at Clontarf in 1014; his descendants became the ruling family of Thomond. In 1890 O'Brien was the sixth most numerous surname in Ireland.

Coat of arms associated with the O'Brien surname
Irish formÓ Briain
Meaning'descendant of Brian'
CountiesClare, Limerick, Tipperary, Waterford
Other spellings4

Origin of the O'Brien name

Woulfe: the family 'derives its name and descent from Brian Boru'. Brian raised his clan, the Ui Toirdealbhaigh, to pre-eminence among the Dalcassians; his posterity became the ruling family in Thomond, held all of Co. Clare and much of Limerick, Tipperary and Waterford, and some were kings of Munster and of all Ireland.[1]

  1. 1002Malachy submits; Brian Boru acknowledged King of Ireland.[2]
  2. 1014Brian Boru killed at the Battle of Clontarf, Good Friday, 23 April.[2]
  3. 1543Murrough O'Brien created Earl of Thomond by Henry VIII at Greenwich.[3]
  4. 1690O Brien listed among Irish septs in Sir James Terry's Book of Arms.[7]
  5. 1848William Smith O'Brien leads the failed Young Ireland rising.[4]
  6. 1890O'Brien ranks sixth in Ireland, about 33,400 people (Matheson).[5]

Where in Ireland

Co. ClareHeart of Thomond: Woulfe says O'Brien possessions included the whole of Co. Clare.[1]
Co. LimerickBranches of Coonagh and of Pobelbrien, whose chief stronghold was Carrigogonnell on the Shannon.[1]
Co. TipperaryBranches of Ara (chief styled Mac I Bhriain Ara) and of Aherlow.[1]
Co. WaterfordO'Briens of Cumaragh, along the Cummeragh mountains between Dungarvan and the Suir.[1]
Co. CavanIn 1890 Cavan had the most O'Briens of any Ulster county.[6]

Notable people named O'Brien

Brian Boru (Brian Borumha)c. 941–1014King of Munster, acknowledged King of Ireland in 1002; killed at Clontarf in 1014.[2]
Murrough O'Brien, 1st Earl of Thomondd. 1551Gave up opposing Henry VIII and was created Earl of Thomond at Greenwich on 1 July 1543.[3]
William Smith O'Brien1803–1864MP born at Dromoland, Co. Clare; Young Ireland leader in 1848; transported to Tasmania; given a free pardon in 1856.[4]

Other spellings

O'Brian · O'Bryan · O'Bryen · Brien[1]

The O'Brien coat of arms

The name O Brien appears in the 'List of Names of Irish Septs as given in the Book of Arms, compiled by Sir James Terry, Athlone Herald (1690)', as printed by Matheson. The list gives sept names only; it does not describe any arms, and it does not mean that everyone named O'Brien is entitled to a coat of arms.[7]

The design shown is a coat of arms associated with the O'Brien surname. In Irish and British heraldry a coat of arms is granted to one person and passes to their heirs; it does not belong to everyone who shares the surname. Many families still use the arms of their name as a symbol of their heritage.

O'Brien crest gifts

O'Brien surname: questions

What does O'Brien mean?

Woulfe gives Ó Briain, 'descendant of Brian', the family taking its name and descent from Brian Boru, King of Ireland.[1]

Are the O'Briens descended from Brian Boru?

Woulfe (1923) says the Ó Briain family 'derives its name and descent from Brian Boru', who was slain at Clontarf in 1014.[1]

Where are the O'Briens from in Ireland?

Thomond: Woulfe says their possessions included all of Co. Clare and large parts of Limerick, Tipperary and Waterford, with branches at Ara, Coonagh, Pobelbrien, Aherlow and Cumaragh.[1]

Is Brien the same name as O'Brien?

Not always. Woulfe lists Brien among the anglicised forms of Ó Briain (with O'Brian, O'Bryan and O'Bryen). He also records a separate surname, Brian (Brian, Bryan, Brien), meaning 'son of Brian', from a Breton personal name introduced into England at the Conquest; that family settled in Kilkenny and Wexford.[1][8]

How common is O'Brien in Ireland?

Matheson's table from the 1890 Births Index places O'Brien sixth in Ireland, with an estimated 33,400 people.[5]

Sources

  1. Ó Briain — Irish Names and Surnames (Rev. Patrick Woulfe, 1923), transcribed, LibraryIreland.com. libraryireland.com/names/ob/o-briain.php
  2. Brian Borumha (Brian Boru) — A Compendium of Irish Biography (Alfred Webb, 1878), transcribed, LibraryIreland.com. libraryireland.com/biography/BrianBoru.php
  3. Murrough O'Brien, 1st Earl of Thomond — A Compendium of Irish Biography (Alfred Webb, 1878), transcribed, LibraryIreland.com. libraryireland.com/biography/MurroughOBrien1stEarlofThomond.php
  4. William Smith O'Brien — A Compendium of Irish Biography (Alfred Webb, 1878), transcribed, LibraryIreland.com. libraryireland.com/biography/WilliamSmithOBrien.php
  5. Principal Surnames in Ireland (table of 100 principal surnames, Births Index 1890) — Special Report on Surnames in Ireland (Robert E. Matheson, 1909), transcribed, LibraryIreland.com. libraryireland.com/matheson/report/principal-surnames-ireland.php
  6. O'Brien — Birth Indexes of 1890 — Special Report on Surnames in Ireland (Robert E. Matheson, 1909), transcribed, LibraryIreland.com. libraryireland.com/matheson/report/births/obrien.php
  7. Names of Irish Septs as given in the Book of Arms compiled by Sir James Terry, Athlone Herald (1690) — Special Report on Surnames in Ireland (Robert E. Matheson, 1909), transcribed, LibraryIreland.com. libraryireland.com/matheson/report/irish-septs.php
  8. Brian — Irish Names and Surnames (Rev. Patrick Woulfe, 1923), transcribed, LibraryIreland.com. libraryireland.com/names/b/brian.php

Note: Matheson's 1890 figures for a surname include its spelling varieties (Matheson, Table Explanation).