Irish names have made their way all over the world, but here are the oldest surnames among them.
Irish surnames are fascinating and steeped in centuries of storied history. Until the 10th century, Irish surnames weren’t passed down between generations.
Instead, surnames were based on the father’s name. Someone was identified as their name, plus ‘mac’, plus their father’s name, with ‘mac’ meaning ‘son of’.
For girls and women, this would be ‘nic’, pronounced ‘ni’. Alternatively, ‘o’ was sometimes used in place of ‘mac’, meaning
descended from’ or ‘grandson’ of. Around the 1100s, people in the upper social classes began taking hereditary surnames that would remain fixed for generations.
The influence of the Norman invasion of Ireland in 1169 on Irish names is undeniable, too.
10. Ó Catháin (O’Kane/Keane) – remains a notable name today
Tracing back to the 11th century, the Ó Catháin family was a notable Ulster clan based in Derry during Ireland’s medieval era. The name means ‘descenedant of the battle-like one’.
While some of the oldest Irish surnames have almost disappeared to extinction, the English versions of this surname, Keane and O’Kane, are still quite prominent today. Two prime examples would be Irish footballer Roy Keane.
9. Ó Ruairc (O’Rourke) – dating back to the 10th century
Ó Ruairc is an ancient Irish name that dates back to the 10th century. The name comes from the personal name Ruairc which is of Old Norse origin.
It is primarily associated with the family that was part of the ancient Gaelic nobility and the Kingdom of Breifne, which covers modern-day Leitrim and Cavan. The chieftans of this clan were known as feirce warriors and nobility in Connacht.
8. Ó Maoldhomhnaigh (Moloney) – possibly found in a 6th century book
Even though this Irish name takes 8th place on our list of the oldest surnames in Ireland, the name Moloney was said to have been found in a book written in the 6th century by Saint Colum Cille.
The Irish version of the name is rarely found today, but Moloney remains a prominent surname across Ireland. One of the most notable Irish people with this surname is Paddy Moloney, co-founder and leader of one of the best Irish traditional folk bands of all time, The Chieftains.
7. Ó Briain (O’Brien) – from Brian Boru
A common name still, this surname comes from the 10th-century High King of Ireland, Brian Boru. Brian Boru famously defeated the Vikings at the Battle of Clontarf in 1014.
It is most commonly believed that the Irish name Brian comes from an old Celtic word, and it is intended to mean “high” or “noble”.
6. Ó hUallacháin (Houlihan) – comes from the Irish word for proud or arrogant
Ó hUallacháin is an old Irish Gaelic surname meaning “descendant of Uallachán”. The name comes from the Irish word uallach, which means “proud” or “arrogant”.
It is the root for several modern English spellings, including Houlihan, Holohan, and Hoolahan. This name is very uncommon today, and you rarely hear it in many places around the world.
5. Ó hEidirsceoil (O’Driscoll) – descendant of the news-bearer
The O’Driscolls were rulers of the Dáirine sept of the Corcu Loígde until the early modern period and their ancestors were Kings of Munster until the rise of the Eóganachta in the 7th century.
The name has an interesting origin, as it means “descendant of the news-bearer” or “go-between”, a compound of the Irish words ‘eidir‘ (between) and ‘scéal’ (story or news).
Historically, this links the clan to the role of interpreters, mediators, or those who spread the word of stories. Perhaps the most well-known O’Driscoll of the modern day is Irish rugby player Brian O’Driscoll.
4. Ó Maolchluiche (Mulcahy) – ancient family from Sligo
This surname comes from an ancient Sligo family who were chiefs of Cairbre. The surname translates to descendant of a devotee or gamester of sport, as the Irish word maol means chief or devotee. while cluiche means game.
3. Ó Canannáin (Cannon) – lords of Tirconnell
This is one of the oldest surnames in Ireland that dates back to 950 AD. The name comes from a family who were lords of Tirconnell from the start of the 10th to the middle of the 13th century.
The name is extremely rare today, but you will find the anglicisation Cannon still scattered around the globe. Perhaps one of the most well-known people around the world with that surname today is American rapper Nick Cannon.
2. Mac an Bháird (Bard) – from a learned clan
Meaning son of a bard, this name come sfrom one of the learned families of late medieval Ireland.
Like many Irish surnames, it has evolved over the centuries, with English versions including McWard, MacEward, and MacAward.
1. Ó Cléirigh (Cleary) – the oldest recorded Irish surname
Largely recognised as the oldest recorded Irish surname, this surname dates back as far as 916 AD. The original family that bore this surname were said to come from County Galway.
The Ó Cléirigh family were part of the same line as Guaire the Hospitable, the famous 7th-century King of Connacht. The surname has been anglicised in various different forms, including Cleary and Clarke.
Like many of the earliest Irish surnames, they often came from a persons job, in this instance descendant of a clerk.
