The most common Irish surname, Murphy is believed to be derived from the old Irish surname Ó Murchadha meaning ‘Son of the Sea Warrior’. Murphys are widely recorded in every corner of Ireland with a variety of spellings – Murphy, Murphie and even Curphy in the Manx form of the name. Murphy is also very prevalent in the US and Britain – where it is the 53rd and 67th most common surname respectively.
Famous Murphys: Cillian Murphy (actor), Eddie Murphy (actor, comedian), Róisín Murphy (singer)
There are several theories on where Kelly came from. The most common is that it is the Anglicised version of the Irish ‘Ó Ceallaigh’. Others believe that Kelly has Scottish roots, despite its strong association with Ireland, with a man of the surname “de Kelly” noted in Scottish Parliament records in the 1300s. Around the same time, though, Kellys were recorded in Galway and Roscommon in the local chieftain's family.
Famous Kellys: Grace Kelly (actress, Princess of Monaco), R. Kelly (singer)
The history of Byrne is well recorded – the surname comes from Co. Kildare, where the clan of Bran, King of Leinster, came from. King Bran died in 1052 but his name adapted with the centuries, becoming Byrne. It also appears in some instances as O’Byrne.
Famous Byrnes: Shane Byrne (former rugby player), Gabriel Byrne (actor)
Ryans originated in Counties Limerick and Tipperary in Ireland. Anglicised from the old Irish of Maolriain, it is believed that Ryan (the “riain” part of the Irish name) comes from an ancient word for water. It was first recorded in Medieval times but believed to have originated well before then.
Famous Ryans: Meg Ryan (actress)
A very regal name, O’Brien dates back as far as the 9th century, to the High King of Ireland, Brian Boru. A powerful and impressive clan in Irish history, the O’Briens commanded high respect in Ireland 1000 years ago. As the centuries passed, O’Briens continued to hold some of the most prestigious offices – including the Earl of Thomond and Viscount Clare.
Famous O'Briens: Conan O’Brien (talk show host)
Coming from the Anglo-Saxon word “waelisc”, Walsh means “foreigner” or “stranger” – Walsh is a very popular Irish surname around the world. Walsh comes with many spellings – Welsh and Walshe being two of the most common. The name also has strong connections to Wales.
Famous Walshs: Bradley Walsh (actor, quiz show host), Willie Walsh (CEO of International Airlines Group), Louis Walsh (TV personality)
O’Sullivans can be traced back as far as the 3rd century, when their descendent King Eoghan Mór ruled over the province of Connaught. Like many on this list, O’Sullivan is Anglicised from the Irish Ó Suileabhán. From the year 1200, O’Sullivans began spreading around Ireland, reaching counties like Kerry and Cork, dividing into separate factions.
Famous O'Sullivas: Gilbert O’Sullivan (singer), Ronnie O’Sullivan (snooker player)
With variants like Connor, Conner, O’Conner and Conor, this Irish surname has evolved more than most. Nevertheless, every variant of the name is descendent from the most famous Connor of all – King Conchobhar of Connaught, who died in the year 971. A name with several regal connections, the last two High Kings of Ireland were O’Connors - Turlough O'Connor and Roderick O'Connor. A thousand years later, the name is still closely associated with Ireland.
Famous O'Connors: Sinéad O’Connor (singer), Joseph O’Connor (novelist)
Doyle’s roots come from the south-east of Ireland – a common name in counties Carlow, Wexford and Wicklow. It is derived from the old Irish phrase “Dhubh-ghall”, or dark stranger. This led to the traditional belief that Doyle was a name that originated with some of the settlers in Ireland a millennium ago – either Anglo-Saxon settlers from Britain or Danish Norsemen.
Famous Doyles: Anne Doyle (newsreader), Maria Doyle Kennedy (actress)
Rounding off the top ten is McCarthy. The prefix “Mc” in any Irish name means “son of” – while Carthy, also spelled Carty, comes from an old word for “loving”. The irony in this case is that the ancient McCarthy clan were well-known for their territory disputes with neighbours. Legend also has it that the name comes from 3rd century King Oilioll Olum – who was a son of Eoghan Mór, meaning McCarthys and O’Sullivans can be traced back to the same clan.
Famous McCarhys: Mick McCarthy (ex-soccer player and manager), Melissa McCarthy (actress)
Order of surnames based on CSO 2014 figures. See Surname Database for information