We are blessed in Ireland to have surnames (last names) steeped in strong traditions and extensive history. Like much of the western world, Irish surnames are hereditary in nature, passed down as each generation takes their father’s name. This patronymic naming convention is still going strong and enables us to trace our roots back generations.
Although largely anglicised today, Irish family names have derived from Irish and Scottish Gaelic and are a melting pot of Norse, Norman, Palatine and Huguenot influences.
Do you have Irish ancestry and an Irish surname? Let us take you on a journey of the most popular surnames by region – you might find your own in there!
We can’t talk about Irish surnames without first mentioning the Mac’s & O’s. In very simple terms, this can be explained as:
There is no distinction between the genders in English – Niall and Sarah are both O’Neill, Niamh and Sean are both McGinn.
For women, the convention is a little different when it comes to spelling names in Irish:
A tragic phenomenon known as “souperism” arose during the Great Famine of the mid-1800s. And as a result, many Irish dropped the O’s and Macs from their names. A conversion method used by Protestant religious societies during this period was to set up soup kitchens for the starving Catholic Irish populace. For them to avail of their services, though, they were expected to convert to the Protestant faith. This led to bitterness among the Catholic Irish towards those who “took the soup.”
A clan, meaning family, came about as a way of uniting people of the same surname under one Kinship. Members came together under the belief they all descended from a common ancestor. For example, the O’Neills descended from one man, Niall of the Nine Hostages, who was apparently the man responsible for kidnapping St. Patrick and bringing him to Ireland. For anyone interested in the O’Neill clan, explore the ancient territory of the O’Neill’s on our Hiking the Causeway Coast & Donegal tour.
The clan’s role was to maintain and defend the native territory of their ancestors, known as a duiche. Some of the most popular clans were the McCarthy, O’Neill, O’Brien and O’Connor’s.
Each clan had various smaller septs, known as sliocht, in their Kinship. These sliocht acknowledged the supremacy of a larger clan. Examples of this are the O’Donovan’s and O’Mahoney’s, whose chiefs paid tribute to the King of the McCarthy Reagh clan of modern-day Cork. Why not travel to lands once held by the McCarthy clan on our Hiking & Island-Hopping trip?
This was how ancient Irish society was organised for centuries until Henry VIII declared himself as King of Ireland in 1542, leading to much disruption of the Gaelic social order and the eventual end of the clan system.
But all was not lost! The legacy of the clan system remains firmly imprinted in Irish life, as Irish people at home and abroad identify strongly with their family names, maintaining an in-built tribalism. So much so that in 1989 the Clans of Ireland was formed in Co. Galway to preserve the cultural history and genealogy of Irish clans. Why not check out the database yourself?
Due to countless waves of emigration over the centuries, Irish surnames can be found far and wide – most notably in the US, Canada, Australia, and the UK.
A lot of surnames were lost in translation on arrival to their new shores as a result of both illiteracy and as well as a concerted desire to assimilate into new communities. Another reason for name changes post-emigration was the phrase “no Irish need apply” appearing in many job advertisements. And so, many emigrants found themselves dropping the Mac & O from their names to sound less Irish and more appealing to prospective employers abroad.
This variety of new spellings in Irish surnames abroad can be a confusing obstacle for those researching their ancestry. You will likely stumble across a variety of spellings of your ancestor’s surname, so it’s worth considering these when doing your research.
Clans aside, here are some of the most popular names in Ireland today by region.
The O’Neill dynasty was once at the forefront of Gaelic life in ancient lands that are now Donegal and Tyrone. They were a prominent family up until the Flight of the Earls in 1607.
This name has travelled far and wide, with variations such as “O’Neal,” “Neill” and “Neil” to name a few, and remains a vastly popular name throughout Ireland. The family seat of the O’Neill’s today is Shane’s Castle, on the shores of Lough Neagh in county Antrim – just one hour from the Giant’s Causeway and 30 mins from Belfast.
From the Giant’s Causeway to the wilds of Donegal, discover the lands that the mighty O’Neills once ruled on the trip, the Causeway Coast and Donegal.
The name “Maguire,” derived from the Irish clan Mac Uidhir, first appeared in the Annals of Ulster in 956 and is said to mean “son of the brown one.” Originally a clan in the province of Leinster, the Maguires moved northwards to the beautiful Lakeland county of Fermanagh, in modern-day Northern Ireland, where they sat as kings for over 300 years. In the US, the surname Meguiar is a supposed variation of this name.
Book a private adventure through Northern Ireland’s coasts and glens to discover the beauty of the north.
Originally “Ap Huw” and attributed to a tribe of Welsh Celts, this name migrated with them when they came to Ireland, becoming a form of the Irish name Ó hAodha, meaning fire.
So, if you know someone with the surname “Hughes” and they have a temper, this might be why! The name “Hughes” is now most commonly found in the lesser-travelled County Monaghan and is largely still very popular in Anglesey, an island off the north coast of Wales.
This name is mostly found in the treasured county of Donegal and roughly translates as “mighty rulers.” It’s an anglicised form of the surname “Ó Donnghaile,” meaning those with this surname are descendants of the clan namesake, “Dónal.” Other variations of the name are “Donnelly,” “O’Donnelly,” and “Donnelie,” to name a few.
The Rock of Doon near Glenveagh National Park in Donegal is the site where the O’Donnells of ancient Ireland chose to inaugurate their chieftains.
Interested in visiting the region? Explore the wilds of Donegal on a bike trip, whisking you away to the ancient seat of the O’Donnells.
The surname “Brennan” is abundant in counties Sligo and Roscommon. It was first recorded in 1159 in the Annals of the Four Masters, referencing the chief of Roscommon, MacBranain. The name is said to mean ‘son of the dark one,’ a nod to the raven hair of the chief. A famous Brennan is the Irish folk-singer Enya, born Eithne Pádraigín Ní Bhraonáin in the Irish-speaking community of Gweedore, Donegal.
Meander the stunning but overlooked County Sligo, once home to the Brennan clan, on a self drive adventure from Sligo to Westport.
Overall, “Walsh” is the 4th most common surname in Ireland and is most plentiful in the mountainous wilds of Mayo. It was brought to Ireland by Norman/Welsh soldiers sometime during the Norman invasion of Ireland in the 12th century.
The Irish for the surname is “Breathnach,” meaning “Welshman”, and would indicate some Welsh lineage for those possessing this surname. Other variants are “Welsh,” “Welch,” “Wallis,” or “Brannagh.”
Discover the remote corners and peaks of Mayo while hiking the mountains of Connemara and Mayo.
Morgan McMahon, one of the earliest recorded US settlers from Ireland, landed in Philadelphia in 1746. The name “McMahon” carries great power in that those with this surname are descendants of the famed Brian Ború – once the High King of Ireland whose legendary deeds ended Viking power in Ireland at the Battle of Clontarf in 1014. The greatest number of McMahons in the country are found in the Munster counties of Limerick and Clare.
Explore the region of Munster, once home to the McMahons, on our trip, hiking Kerry and Clare.
Supposedly the oldest recorded surname in Ireland, it derives from the Irish surname “Ó Cléirigh” – with Cleirigh meaning “clerk” or “cleric”, hinting that the Clearys of today are descendants of a learned scribe or religious man.
Today, the largest number of Clearys found outside of Ireland are located in the US state of California. A notable variation of “Cleary” is the name “Clarke.”
Bike through Galway and traditional Cleary country while cycling Ireland’s West Coast.
“Murphy” lends its name to the finest Irish stout in the country (though be careful, don’t tell Guinness lovers this). Not only is it the most popular name in Cork, but it’s also the most common name in Ireland as a whole. Deriving from the Irish O’Murchadh, the name Murchadh loosely translates as “sea battler” in English.
Other variations of the name “Murphy” are “Morrow,” “McMorrow,” and “McMurrough.” At the time of writing, it is the 58th most common surname in the US.
Island hop through the land of the Murphys on hiking and island hopping in Cork and Kerry.
Outside of Ireland, the name “O’Sullivan” is most common in England and Australia. Within Ireland, it is the third most frequently found name in the country – most popular in Kerry. There are two distinct clans: the O’Sullivan Mór of Kerry and the O’Sullivan Beara of Cork (Beara peninsula).
Both clans are known to have fought fiercely against English troops in the early 1600s alongside their allies. The name comes from the Irish O’Suileabhain and is said to mean “one-eyed” or “hawk-eyed”.
Climb to new heights and explore the region associated with the O’Sullivans on our Kerry Mountains trip.
A wildly popular surname in the counties of Limerick, Tipperary, Waterford and Wexford, it was first used by Donogh Cairbre O’Brien in the 13th century. Meaning “descendent of Brian”, those with this surname can also claim lineage from the once High King of Ireland, Brian Ború.
The US city you’re most likely to encounter an “O’Brien” is in Boston, Massachusetts – Conan O’Brien is a notable resident that springs to mind!
When you think of Butlers now, you would be forgiven for thinking of chocolate. There are 39 Butlers Chocolate cafés worldwide, with the most famous being on Grafton Street in Dublin. With the Anglo-Norman invasion of the 12th century came the name “Butler.” It derives from the Huguenot “boteillier,” meaning bottler or cupbearer.
Today it is largely found in the Marble County of Kilkenny and descendants can claim lineage from a powerful dynasty that was once known as the Dukes of Ormond.
Wander Ireland’s Ancient East on our self drive of the same name.
The origins of this surname are a little hazy, but it is largely suspected to be of Norse origin. Mainly due to the Irish name Dubhghaill, translating as the “dark stranger or foreigner” in reference to the Danish Vikings of the 8th and 9th centuries. It is most popular in Dublin and the surrounding counties of Wicklow and Kildare.
Hike the Wicklow Way along the ancient stomping grounds of the Doyle clan.
In south Wicklow, nearing the end of the Wicklow Way trail, there is such an abundance of Byrnes that they must distinguish the various families by nickname – the rabbits, badgers, fish, pigs and hares, to name a few.
Identifying families by obscure nicknames is standard practice across the country, given the small population! It could be argued that “Byrne” is an anglicised version of “O’Brien,” and it likely is. But it’s one that’s taken on a life of its own.
Want more flexibility? Walk the Wicklow Way self guided to travel at your own pace.
If you are interested in exploring Ireland and your family’s own Irish origins, contact our friendly team to book a custom tour.
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