O’Brien: surname meaning, origin and popularity, explained

Irish surnames often have a rich history behind them. Due to mass emigration years ago, Irish people have a presence all over the world. In this article, we’re going to look at the O’Brien surname, as well as its meaning, origin, and popularity.

You might know an O’Brien personally, or maybe you recognise the surname from a famous person somewhere across the world.

We’re here to find out the origin of the O’Brien surname. Not only this, but also why it is so popular, how you say it, and what the name actually means.

You might recognise a famous O’Brien or two while we’re at it. Let’s take a look at the O’Brien surname, its meaning, origin, and popularity, explained.

Ireland Before You Die’s overview of facts about the surname O’Brien

  • The surname of O’Brien is Irish in origin and translates to “descendant of Brian”. The word Brian means “force” or “strength”. 
  • The O’Briens come from powerful origins. They have a historic connection to Irish royalty. Indeed, Brian Boru was one of the most famous High Kings of Ireland. He united many Irish tribes against Viking invaders during the Battle of Clontarf. 
  • Furthermore, the O’Brien’s had a prominent influence and held sway over the province of Munster in southern Ireland. This influence was particularly strong in counties Clare and Limerick. 
  • There are also many variations to the name of O’Brien. These include – O’Bryan, O’Brian, and Bryan, amongst others. 
  • Due to the likes of the Irish Famine, which there are some horrifying facts everyone should know of, many O’Brien’s emigrated from Ireland. Thus, there is a widespread Irish diaspora of O’Brien’s in countries such as Canada, Australia and the United States, which saw the development of the Celtic connections between Ireland and Boston.

O’Brien – where does it originate and what does it mean?

The surname O'Brien comes from Brian Boru.
Credit: commons.wikimedia.org

The surname O’Brien is the English form of the Irish surname, O’Briain. It has royal origins as it is said to derive from the 10th-century King of Ireland, Brian Boru. He is one of the most powerful kings in the history of Ireland. 

The ‘O’ at the start of an Irish surname means ‘descendant of’. In this case, descendant of Brian, the Irish king. O’Brien means ‘exalted one’ or ‘eminence’.

The O'Brien surname is today mostly popular in Dublin and Munster.

The O’Brien surname is a popular one in Ireland. In fact, it is among the ten most popular Irish names. Today in Ireland, O’Brien’s are most commonly found around Dublin and in the Munster counties of Clare, Limerick, and Cork.

Brian Boru’s reign as King of Ireland ended with his death at the Battle of Clontarf in 1014. Boru was survived by his harp, which went on to become the national emblem for Ireland, as well as the logo for Guinness!

If O’Brien is your surname, this is a pretty cool origin story.

LEARN MORE: Read our article on the top 10 facts you never knew about Irish surnames

Pronunciation – how do you say it?!

Credit: YouTube / Emma Saying

Ó Briain, O’Brian, O’Bryan, O’Bryen, O’Brien, Brien; the name has changed and evolved since its early origins centuries ago, and therefore so has how it is said.

Sometimes, this can mean it can be quite tricky to pinpoint which way to say the surname correctly.

If you see any of the anglicized versions of the surname, like O’Brien, O’Bryan, O’Brian, or O’Bryen, it will most commonly be pronounced ‘o-bry-ahn’.

On the other hand, if the name is spelled the typical Irish way, ‘Ó Briain’, it is more likely to be pronounced ‘o-brain’.

Famous O’Brien’s – there are a few

The Irish surname O'Brien.

Due to the famine, conflict, and economic problems across the centuries, mass emigration from Ireland has meant that Irish people and their second names, some of which are even Viking in origin, have sprouted roots all over the world.

There are therefore many Irish families both at home and abroad in the Irish Diaspora with this surname. In turn, this means there are a lot of famous O’Brien’s out there across several parts of the world.

Edna O’Brien

Edna O’Brien is an Irish short story writer and Irish novelist. She was prominent in the 1960’s when she wrote novels that outlined the inner feelings of women in relation to men in society, something widely avoided back then.

In fact, shortly after publication, her books were deemed so scandalous that they were actually banned, and, in some cases, burned. She is considered a legend in the literary world for challenging norms and breaking down societal barriers.

Dara O'Brian and Conan O'Brien are famous people with the surname O'Brien.
Credit: Flickr / IAB UK and commons.wikimedia.org

Dara Ó Briain

Another famous Irish O’Brien is comedian Dara Ó Briain, who spells his surname the Irish way.

He is best known for performing stand-up comedy gigs all over the world, as well as hosting panel TV shows like Mock the Week.

Conan O’Brien

Conan O’Brien was born in the US to Irish-Catholic parents. His ancestors were said to move to the United States from Ireland some 150 years ago.

He is best known for being the host of late-night talk shows including Late Night with Conan O’Brien and The Tonight Show.

Dylan O’Brien

Another famous face with the surname O'Brien.
Credit: commons.wikimedia.org

Dylan O’Brien is an American actor. He is known for films such as the Maze Runner franchise and the hit TV series Teen Wolf.

He gets the O’Brien surname from Irish heritage on his father’s side.

So, there we have it. The O’Brien surname, its meaning, origin, and popularity, explained. How many of the famous O’Brien’s do you recognise, and did you already know what the surname meant and its origins?

READ MORE: Top 10 coolest Irish last names (surnames), RANKED

Notable mentions

William Smith O’Brien: William Smith O’Brien was an Irish Nationalist Member of Parliament and leader of the political and cultural movement of Young Ireland in the 1840’s. William O’Brien strongly encouraged the use of the Irish language.

John O’Brien: John O’Brien was an American author. His most famous novel, Leaving Las Vegas, was published in 1990 and made into a film of the same name in 1995.

O’Brien’s outside of Ireland: Immigration records show that today, due to emigration, there are more O’Brien’s outside Ireland than within, with the largest number being in the United States.

READ: For more on Irish second names, have a read of IB4UD’s article on the top 100 Irish surnames/names (info & facts)

Your questions answered about O’Brien and Irish surname

If you have read our article about O’Brien and the Irish surname and you still have some questions, then you have come to the right place! Below, we have outlined the most frequently asked questions about this topic.

The O'Brien’s were one of the most significant clans throughout Irish history. The clan associated with the O’Brien name came from Brian Boru of the Dál gCais (Dalcassian) clan.
Credit: commons.wikimedia.org

What clan does O’Brien belong to?

The O’Brien’s were one of the most significant clans throughout Irish history. The clan associated with the O’Brien name came from Brian Boru of the Dál gCais (Dalcassian) clan.

What is the oldest Irish surname?

The oldest known Irish surname and is O’Clery (O Cleirigh). It is the earliest known because it is recorded that the Lord of Aidhne, who had this name, died in County Galway back in the year 916 A.D. 

What is the most popular surname in Ireland?

The O’Brien surname is popular, but not the most popular surname in Ireland. This would be Murphy. 

Who were members of the O’Briain dynasty? 

These would include Diarmait Ua Briain, Domnall Mór Ua Briain, and Murchadh Carrach Ó Briain. 

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