Irish Last Names (Surnames): They Offer Clues About Family History and Heritage!

Our favorite of all Irish last names - the name 'Grady' - derives from the ancient Irish name Ó Grádaigh, meaning 'son of Gradaigh.  The word Gradaigh itself means 'noble' in the Gaelic language.

Irish Last Names - Grady Family Crest

Originating in Ireland the O Gradaigh (O'Grady) family name migrated to England, and eventually to the US as well, becoming 'Grady.'

I share that bit of trivia with you, because I have found that knowing a bit about the meaning and history of our name opens up many new ways to express our Irish side.  

Great ways to do this include displaying a framed Irish family crest, creating customized clothing, purchasing custom tableware (coffee mugs), jewelry and so on.

If that interests you, read on!  

What's in a Name?

Irish last names are common throughout the world. However, in traditional Irish society surnames were rarely used and single names were actually more common.

This changed around the eleventh century as the population grew and it became necessary to have a second name, a surname.

It was at this time that the very traditional surnames that we associate with the Emerald Isle began to emerge.

Often these names had one of two prefixes at the beginning - an ‘O' meaning ‘grandson of', or ‘Mac' meaning ‘son of'.

The importance of ancestry in Irish society is demonstrated by the fact that surnames were used as a way of identifying that you were descended from your forefathers.

Search for Family Name Button

How Did it All Start?

The first Irish last name in recorded history is O' Cleirigh (pronounced O' Clear Ee). The Anglican version which is more commonly used today is actually Mc Clery or O' Clery.

This surname is likely associated with the occupation of a person's ancestors as the word comes from the word for Church Clerks.

Other professions are also often associated with surnames. These include the surname McGowan, which is an anglicised version of Mac Gabhainn (pronounced Mc Gow An) meaning a smith.

In many ways the genesis of Irish last names is quite similar as in other countries such as England where they often represented a profession.

Another Source of Irish Last Names...

Another common background for Irish surnames is Irish history or mythology.

O'Brian was one of the most common surnames of the eleventh century and this derived from the importance of Brian Boru, a famous High King who defeated the Vikings after almost 200 years of intermittent Viking attacks.

This is one of Ireland's most famous heroes and the name Brian, meaning noble or strong, is reflected in both Irish Christian names and also Irish last names.

Like Irish first names, surnames were also influenced by English rule in Ireland.

The penal laws demanded that every baby be given an Anglican name. In many ways therefore the most common Irish surnames throughout the world today are actually the anglicised versions as opposed to the traditional Gaelic versions of the name.

Irish surnames are common in countries such as the USA or England where many immigrants moved to after the Great Famine of the 1840s and subsequent immigration throughout the 19th and 20th Centuries.

Some of the most common Irish last names include:

O' Connor

Pronounced /O Con' er/.  This Irish last name is the anglicised version of ó Conchobhair which means the patron of warriors, a clear reference to the Irish mythology of warriors such as the famed Brian Boru.

Perhaps the most famous Irish person with this surname is Sinead O'Connor, an Irish singer whose song ‘Nothing Compares to You' was extremely successful. She is also well known for her somewhat controversial opinions on issues such as religion.


Pronounced /Mer' fee/. This surname is from the traditional Gaelic name ó Murchadha which means sea battler.

Irish history also includes over two hundred years of ongoing Viking invasions from the sea and therefore the idea of sea battles is extremely important historically.

Not only is Murphy one of the most common surnames in Ireland but it is also amongst the top 60 most common names in the US demonstrating the significance of Irish ancestry in the United States.


Pronounced /o BRI' en/.  Brian Boru was one of the most famous heroes in Irish history. It was he who defeated the Vikings once and for all.

The name actually comes from the Gaelic ó Briain which means noble.


The surname Walsh is also extremely common in Ireland and comes from the Gaelic word Breathnach meaning Welshman.

Gaelic history is linked to other nations such as Wales and Scotland. These countries have a shared Gaelic heritage and therefore many Welsh would have travelled to Ireland during Ireland's history.

The most famous Welsh man ever to set foot on Irish soil is most likely St Patrick, the patron saint of Ireland. He is celebrated around the world for being synonymous with Ireland and yet he was actually from Wales originally.


Pronounced /Doil/. This surname comes from the Gaelic surname ó Dubhghaill meaning "dark foreigner."

Areas of West Ireland received a number of Spanish into their communities, and towns such as Spanish Point on the West Coast are a reference to these dark haired foreigners.

Perhaps the most famous Doyle is Roddy Doyle whose novels on life in Ireland such as The Commitments have been successfully made into films.

Irish Last Names - Kennedy Postage Stamp


This name needs little pronunciation and is famous across the world for the Kennedy family, an Irish American dynasty who are practically royalty in American history.

As a family they have had their share of fortune, romance and also tragedy. The most famous example, of course, is the assassination of President John F. Kennedy in 1963.

The surname is an Anglicisation of the Gaelic name ó Cinnéide meaning helmet-headed, once again a reference to the legends of battles in Irish history.


This surname comes from the Gaelic surname ó Conghaile which means "fierce as a hound."

James Connolly was certainly fierce in his determination to free Ireland from English rule and is considered a hero for his participation in the 1916 Easter Rising in Ireland although he was executed for his role in the rebellion.


This surname comes from the Gaelic ó Domhnaill meaning world-mighty.

Although he might not be world-mighty as his name would suggest, Daniel O'Donnell is still one of the most famous crooners in Ireland today and his concerts have people travelling from all over to attend, especially the grannies who love this blue-eyed boy's songs.


Who could forget Ireland's participation in the 2002 World Cup? Perhaps the most memorable part of the World Cup was the early exit of the Irish Captain Roy Keane due to his disgust at the state of the team's accommodation and practise pitches.

The other Keane, Robbie, stayed on however and scored a goal in the last few minutes of Ireland's final game before their quarter final exit from the tournament.

Keane comes from the Gaelic surname Mac Catháin.

Interesting!  What's Next?

At Irish Expressions, our our goal is simple: to provide you with a unique Irish experience, on demand, wherever you are in the world.

If you have enjoyed our section on fun Irish trivia and customs, you have probably been exposed to many of the most exciting traditions that Ireland has to offer!

Will that entice you to visit Ireland - or to return if you have already been? 

We hope so!  

But even if that is not possible, you can still enjoy the magic of Ireland in these pages.  Check out the links at the top of the page for simple instructions on how to explore Irish landmarks, sing Irish songs, enjoy Irish food, and much more!

Your Personal Irish Expression

One way to share your love of Ireland is by displaying your family coat of arms (family crest).  A very personal symbol of the stories and accomplishments of your ancestors can adorn clothing, kitchenware, wall art, personal accessories and so much more. 

Want to have a look?  Our friends at House of Names can help! 

Tap the button below and see your family crest for free!

Search for Family Name Button

Want to Feel More Connected to Ireland?  Here's How!

At Irish Expressions we believe everybody – well almost everybody! - has an "Irish side."  So how nice would it be to have access to a fun, free Irish experience, on demand, wherever in the world you happen to be?

Over the years we have compiled many free, downloadable resources including lyrics, recipes, games, jokes, blessings and much, much more.  Would you like to receive them ALL for FREE?  Simply share your email for instant access!


* indicates required

A Note from Bruce

If you would like to see more from Irish Expressions, you can find us on Facebook and Pinterest. You can also communicate with us using our contact form here. 

And of course you can always reach out to me directly at

However you choose to connect, we would love to hear from you!  Meanwhile, thanks for visiting!  I hope that we will meet someday, in person or online, and you can tell me about your own connection to the Emerald Isle.

Until then, best wishes -

Bruce Grady, and the team at