is a common surname of Irish origin.
The name is Gaelic, and its original language version is Ua Briain or Ó Briain (pronounced: Ew-Breen/Oh-Breen), meaning 'descendant of Brian'. It carries the sense ‘eminence’, i.e. ‘exalted one’. The Brian referred to is in most cases the ancient Irish king Brian Boru, or in Gaeilge - Brian Bórumha mac Cennétig.
This O'Brien family ruled over Munster after Brian Boru's death, and later supplied the rulers of Thomond until the area became incorporated into the English holdings in Ireland in the Tudor period (but see the de Clare family).
The O'Brien rulers were then given the titles of Earl of Thomond and Baron Inchiquin, the latter of which survives today and is held by the descendants of the ancient rulers.
Two mottoes have been associated with the O'Brien clan: firstly, Vigueur de dessus: 'Strength from above' and secondly, 'Lamh laidir an uachtar' 'The strongest arm uppermost'
Other variants of this surname are O'Bryan, O'Brian, O'Breen', Breen, Bryant ("T" for Thomond) and many more.
Places named O'Brien
People named O'Brien
- Aidan O'Brien, Irish race horse trainer
- Alex O'Brien, professional American tennis player
- Andy O'Brien (footballer), Irish association football player
- Billy O'Brien (1860 – 1911), American baseball player
- Bronterre O'Brien, (1805 – 1864), British Chartist
- Cathy O'Brien, purported American child-slave/sex-abuse victim
- Clinton O'Brien (b. 1974), Australian rugby league footballer
- Conan O'Brien (b. 1963), US comedian and talk show host
- Danny O'Brien (b. 1969), British writer and digital rights activist
- Dave O'Brien, American sportscaster
- Dave O'Brien (actor) (1912 – 1969), American film actor
- Dermod O'Brien (1865 – 1906), Irish painter
- Ed O'Brien, (born 1968), English musician
- Edward O'Brien (Irish republican), Provisional Irish Republican Army (IRA) volunteer
- Edna O'Brien, Irish novelist
- Edwin Frederick O'Brien, Archbishop of Baltimore
- Erin Joanne O'Brien (b. 1935), American actress
- Erin O'Brien (writer), American writer
- Eugene O'Brien, actor of the silent film era
- Fergal O'Brien, Irish professional snooker player
- Flann O'Brien, pen name of Irish novelist and satirist Brian O'Nolan
- George O'Brien (actor) (1899 – 1985), American silent movie actor.
- George O'Brien (cricketer) (born 1984), Bermudian cricketer
- George O'Brien (footballer), former Southampton F.C. footballer
- George O'Brien (painter) (1821 – 1888), New Zealand painter
- George Thomas Michael O'Brien, former governor of Fiji
- George H. O'Brien, Jr. (1926 – 2005), Korean War Congressional Medal of Honor Recipient.
- George M. O'Brien (1917 – 1986), member of the U.S. House of Representatives
- James O'Brien, further disambiguation page
- Jeremiah O'Brien (1744 – 1818), US Navy officer of the American Revolutionary War.
- Jim O'Brien, further disambiguation page
- John O'Brien (soccer), American soccer player
- John O'Brien (marine artist) (1831 – 1891), Canadian painter
- John P. O'Brien, Mayor of New York City
- Kate O'Brien, British fashion & television make-up artist
- Katie O'Brien, British female tennis player
- Keith Michael Patrick O'Brien, current Roman Catholic Cardinal Archbishop of Saint Andrews and Edinburgh
- Kerry O'Brien, further disambiguation page
- Larry O'Brien (1917 – 1990), American politician
- Larry O'Brien (Canadian politician), Canadian entrepreneur and politician; Mayor of Ottawa, late 2006 to present
- Mark O'Brien (Ontario politician), Green Party candidate in the 2004 Canadian federal election
- Michael O'Brien (swimmer) (born 1965), American freestyle swimmer
- Mick O'Brien (musician), Traditional Irish Musician
- Miles O'Brien (journalist), journalist and CNN anchor
- Patrick O'Brien, further disambiguation page for people with forename Patrick or Pat
- Richard O'Brien (born 1942), Rocky Horror Picture Show writer and actor
- Richard Baptist O’Brien (1809 – 1885), Irish priest, author and nationalist
- Robert O'Brien (auto racer), American racing driver
- Robert C. O'Brien, pen name of Robert Leslie Conly (1918 – 1973), American author and journalist
- Shauna O'Brien, American erotic film star.
- Soledad O'Brien, American television journalist
- Stephen O'Brien, UK conservative politician for Eddisbury
- Stuart O'Brien, lead guitarist of rock band Amnezia
- Terence Albert O'Brien (1600 – 1651), beatified Irish bishop
- Thomas J. O'Brien (Illinois), Illinois politician
- Thomas J. O'Brien (Massachusetts), Massachusetts State Representative
- Thomas J. O'Brien (Michigan) (1842 – 1933), Michigan politician and U. S. ambassador
- Tim O'Brien (author) (born 1946), American author
- Tim O'Brien (musician) (born 1954), American musician
- Tom O'Brien (UK politician) (1900 – 1970), British trade unionist and Member of Parliament
- Tom O'Brien (19th century baseball player) (1860 – 1921), 19th century baseball player
- Tom O'Brien (outfielder/infielder) (1873 – 1901), baseball outfielder/infielder
- Tom O'Brien (actor) (b. 1965), American film actor
- Tom O'Brien (football coach) (b. 1948), American college football coach at North Carolina State University.
- Tommy O'Brien (1918 – 1978), baseball outfielder
- Vincent O'Brien, Irish race horse trainer
Fictional people named O'Brien
Ships named O'Brien