Select O'Brien Surname Genealogy

The early history of the O'Brien clan is as a Dalcassian tribe in SW Ireland and then with Brian Boru, the legendary king of Ireland who defeated the Norsemen at Clondorf in 1014 but died in the process.  The Ui Braians ruled over Munster after Brian Boru's death and, as O達riens, emerged as one of the chief dynastic families of Ireland.

Today, due to emigration, there are more O'Briens outside Ireland than within, with the largest number being in America.  
There are many name variants of O達rien around the world, including Bryan, McBryan, O'Brian, O'Bryan, Bryant, and Breen. 

Select O'Brien Resources on The Internet

Ireland.   The Rock of Cashel in Tipperary was the traditional seat of the Kingdom of Munster, which the O'Briens would hold until the 12th century.  After that time the territory was divided and they ruled over the kingdom of Thurmond in present-day Clare instead.  

Their ancestral home in Thurmond was Dromoland castle.  The O'Brien's rule would last until 1542 when Morrough O'Brien surrendered its sovereignty to the new English kingdom of Ireland under Henry VIII. 

Over the subsequent centuries there were to be many O'Brien branches.  The Earls of Thurmond, representing the main descent, did tend to side with the English.  Other O達riens, although they had accepted English titles, often ended up opposing the English cause: 
  • Murrough O'Brien, the Earl of Inchiquin, having supported the English in 1641, switched sides and left Ireland for France and French service in 1650, although his grandson was later to return in 1703.  
  • while the Viscounts Clare left in 1690 and never returned.  They raised the famous Irish brigade known as Clare痴 Dragoons and were fighting for France until the last of them died in 1774. 
The O'Briens at Comeragh castle in Waterford were almost wiped out by Cromwell in 1656.  After taking the castle, he hanged four of the O達rien brothers.  The fifth, John, managed to escape and from him came the O達riens of Ballyetragh. 

The history of the O'Brien clan, up to the end of the 18th century, was first compiled by John O'Donoghue in the book he published in 1860.

In the 19th century, from an O達rien Clare line, came William Smith O'Brien, an Irish nationalist and one of the leaders of the Young Ireland rebellion of 1848.  This led to his arrest, trial, and transportation to Australia. Other O'Briens of varying backgrounds were also to become engaged in the cause of Irish nationalism at this time. 

Today in Ireland, O達riens are mainly found outside Dublin in the Munster counties of Clare, Limerick, and Cork.  

America.   A number of O'Briens came to America in the second half of the 18th century, including Morris O達rien who came to Machias in Maine.  His son Captain Jeremiah O達rien was one of the early American heroes of the Revolutionary War.  In 1775 he captured a British armed schooner off Machias in the first naval engagement of the war.  His son Jeremiah ran a lumber manufacturing and shipping business in Machias and was active in local politics. 

Born in Ireland in 1827, Hugh O達rien moved with his parents to Boston when he was five.  He prospered there as a printer.  In 1885, he took the office of mayor of Boston, the first Irish-born and the first Catholic to do so in a city previously run by native-born Protestants.  A much later Boston celebrity is the talk-show host Conan O達rien who grew up in a middle-class family in Brookline.  His forebears had immigrated to Boston from county Kerry at the time of the potato famine

Canada.  The O達rien name in various forms was evident in Newfoundland by the late 18th century.  John O達rien came to St. John痴 around 1818.  A dairy farmer, he built Thimble Cottage in the outskirts of the town.  It still stands, with the third generation of O達riens living there. 

O達riens were also part of the Irish community in Antigonish county, Nova Scotia.  The 1838 census listed O達riens in Dorchester and Tracadie townships.  Richard Baptist O韮rien, later a fervent advocate of Irish home rule, spent time as a priest in Antigonish county in the 1840痴.  Michael J. O達rien, the railway industrialist, was born at Lochaber in 1851.  He and his son Ambrose were influential in the founding of the Montreal Canadiens and the National Hockey

Select O'Brien Miscellany

If you would like to read more, click on the miscellany page for further stories and accounts:

Select O'Brien Names

Brian Boru, the legendary 10th century Irish king, left his name to the O'Brien clan.
Murrough O'Brien, known as Murcha of the Burnings, played a controversial role in mid 17th century Irish politics.  He was made President of Munster for expelling the Catholics and then became a Catholic himself.
William Smith O'Brien was the 19th century Irish nationalist who led the 1848 Young Ireland uprising.
William O'Brien was the Irish nationalist who founded the United Irish League, the forerunner of Sinn Fein.
Edna O'Brien is an Irish novelist and short story writer who novels were first banned in Ireland.
Aidan O'Brien is a very successful Irish horserace trainer.
Conan O'Brien is an American comedian and late-night talk show host.

Select O'Briens Today

  • 37,000 in the UK (most numerous in Lancashire)
  • 60,000 in America (most numerous in New York)
  • 108,000 elsewhere (most numerous in Ireland)

Select Surname List

Adams Ellis Johnson O'Connor
Allen Evans Jones O'Sullivan Shaw
Anderson Fisher
Kelly Parker Simpson
Bailey Foster Kennedy Perry Smith
Baker Fox King Peterson Stevens
Barnes Fraser 
Lee Phillips Stewart
Bell Graham Lewis Powell Taylor
Bennett Gray Marshall Price Thomas
Brown Green Martin Reed
Griffiths Mason      
Reynolds Turner
Campbell Hall McDonald Richards
Carter Hamilton Miller  Richardson Walsh
Chapman Harris Mitchell Roberts Ward
Clark Harrison
Moore Robertson Watson
Collins Henderson Morgan Robinson White
Cook Hill Morris Rogers Williams
Cooper Howard Murphy Ross Wilson
Cox Hughes Murray Russell Wood
Davis Jackson Nelson Ryan Wright
Edwards James O'Brien 

For other surnames check the surnames2 page where there are to be found the history and genealogy for more than 800 surnames.

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