Irish Family Names and what they Mean

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Irish Family Names - What do they mean?

Believe it or not, up until the tenth century there was no such thing as a surname in Ireland. The people had no need for them because the population was so small and nobody moved very far from where they were born. Everyone was known by their 'first' name only, and problems only arose if someone with the same name showed up in the same place – which barely ever happened because the population was so small and nobody moved around!

Instead, people identified themselves by what clan or tribe they belonged to. When Christianity began to hold sway over the Irish people, some began to add the name of the religious saint they followed after their own name, with the word 'giolla' or 'maol', meaning 'follower', in between. So 'Sean Giolla Mhairtin' meant 'Sean, follower of Saint Martin', now known as the surname Gilmartin. As the population of the island grew it became necessary to add 'mac', meaning 'son of' to the start of the list as well, and after that, 'ó', meaning 'grandson of'. This is where the common 'Mc' and 'O' in most Irish surnames comes from. Almost all Irish family names were created between the eleventh and twelfth centuries.

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Things get more confusing with different branches of certain family names. For example, an O'Brien may have had a son and named him Mahon O'Brien, meaning Mahon, son of O'Brien. But going on that tradition, Mahon's sons would have had to call themselves McMahon-O'Brien (son of Mahon, grandfather of O'Brien), so to keep things simple they would have adopted McMahon only. Then the children of these McMahon sons would have just adopted that name as hereditary, but would still be direct descendants of O'Brien. Just to make things even more complicated, certain branches of clans spread out to different parts of the country but kept the original name, which is way many people researching their Irish roots are surprised to find that although their McMahon grandparents came from Galway, their ancestors are actually O'Briens from Dublin!

Top 10 Irish Family Names

According to the Irish Genealogical Society International, the most common Irish surnames are Murphy, Kelly, O'Sullivan, Walsh, Smith (which is actually of English origin), O'Brien, Byrne, Ryan, O'Connor and O'Neill. But what did these families do to become so great and have their name so widespread?

Murphy: There are over 50,000 Murphys in Ireland alone and many more around the globe. It is by far the most widespread Irish surname and although it is usually associated with Munster in the south of Ireland, historically the Murphys hailed from Leinster, especially county Wexford. The name started out as O'Murchadha or MacMurchadha, but the anglicised versions of O'Murphy and McMurphy are not very common these days. Murchadha means 'sea warrior', leading many to believe that the Murphys had ancestral links to the Vikings.

A branch of the original Murphy line, the McMurroughs, gave rise to the infamous King of Leinster Dermot McMurrough. After kidnapping another King's wife, he was forced into exile and appealed to King Henry II of England for military aid. The Earl of Pembroke, better known as Strongbow, arrived and took control, eventually claiming the King of Leinster title for himself after Dermot's death and starting a conflict between Ireland and England that lasted for the next several hundred years.

Kelly: The Gaelic version of this name is Ceallach, meaning 'troublesome'. Although the name is attributed to several different clans all over Ireland, Ceallach was most likely the name of their original common ancestor. The most well-known branch was the O'Kellys of Ui Maine, who get several mentions in the ancient 'Annals of the Four Masters' and were named as one of the 'dangerous septs' by the Galway Corporation in 1518. It seems like the 'troublesome' name was particularly apt since one of the most famous Kellys is the Australian outlaw Ned Kelly. His parents came to Australia from counties Antrim and Tipperary, and along with his brother Dan, he led a gang of criminals and committed a series of major robberies through Australia between 1878 and 1880.

O'Sullivan: The O'Sullivan name was most common in Munster, and means either 'one-eyed' or 'hawk-eyed'. There are over 30,000 O'Sullivans in Ireland today and it is said that O'Sullivans are descendants of the mythical Eoghan, thought to be one of the original Gaelic invaders. After 1200 there were two main branches, the O'Sullivan Mor branch of Kerry and the O'Sullivan Beare branch of Cork. In 1602 they were one of the leading families to fight for Hugh O'Neill in his rebellion against Queen Elizabeth I, and some later emigrated to Spain during the 'Flight of the Earls'. One of the O'Sullivan Beares became a prominent figure in the Spanish army and gave the name the high prominence it has today.

Walsh: The name Walsh in Gaelic is 'Breathnach', and literally means 'Welshman'. There are a variety of other Anglicised names derived from Breathnach such as Brannagh, Brannick, and many more. It is another Irish family name that has several different and separate branches throughout the country, and it is thought that this is because anyone with a Welsh ancestor was branded with the name regardless of the rest of their family tree. The Walsh name was especially common in the south-east of the island in counties Wexford, Waterford, Kilkenny, and Tipperary. This doesn't seem like much of a coincidence at all when you consider that the south-east is the nearest point to Wales.

Smith: Smith is actually an English surname, not an Irish one, but it's common in Ireland nonetheless and is also the most common surname in England. The Irish version of the name is MacGabhain or McGowan, and both versions are prevalent in the Northern parts of the country and slightly further South in Cavan, Sligo etc. The Smith name originally comes from the Anglo-Saxon word for 'smite' or 'strike', which could have referred to either a blacksmith or a soldier in battle. The name is likely to have become widespread in Ireland after the Anglo-Norman invasion.

O'Brien: The O'Briens were one of the most powerful clans in Ireland. The majority of them originated in Munster, particularly county Clare. The name was made famous by Brian Boru, who was King of Munster and later became the High King of Ireland, the richest and most respected person in the country. He was known as a great warrior and successfully won scores of battles. When the Normans invaded the coast of Dublin in 1014 (one of the most important battles in medieval Irish history) he successfully beat them too, although this one finally cost him his life.

Byrne: Byrne comes from the Irish 'O'Broin', meaning 'raven'. The first known Byrnes (or O'Byrnes as they were more likely known) came from county Kildare and claimed to be descendants of Bran, who was the King of Leinster until his death in 1052. They were one of the more powerful families in this area right up until the Norman invasion of 1169. After that, they were forced across to the Wicklow mountains and became known for showing strong resistance to foreign influences and being the most passionate patriots in the country. They vigorously defended their territory from any foreign forces and were still naming chieftains up until the 1600s, long after the old system of Kings and territories had died elsewhere.

Ryan: The meaning of the name Ryan is somewhat difficult to pin down. There are several different Gaelic translations of the name ranging from 'Maoilriain' ('follower of Saint Righian') to the old Irish word for water, little prince, and even sluggish or dilatory. There is also another Anglicised version of the name, Mulryan, although this is relatively uncommon these days. The original clan came from counties Limerick and Tipperary. It is generally accepted that the Ryans are descended from Milesius, King of Spain and that the founder of the family was Fiacha Baiceada, son of Cathire More who was King of Ireland in 144 AD. A second branch from county Carlow and other parts of Leinster are from a different descendant entirely; their name was O'Riain and their lineage was from the barony of Idrone.

O'Connor: O'Connor is one of the oldest and most important family names in Ireland. O'Connors are direct descendants from Conchobhair (or Conchuir as he was sometimes known), who was King of Connacht until 971 AD. He in turn was allegedly a grandson of Milesius, King of Spain. The last two High Kings of Ireland were from Conchobhair's bloodline - Turlough and Roderick O'Connor – so it can be said the O'Connors are the last royal family of Ireland. The translation of the name is not quite so royal, however, as 'cu' means 'hound' and 'cobhar' means desire... so that could be loosely translated as 'dog lover!' The name arose from five different regions of Ireland; Connacht, Kerry, Derry, Offaly, and Clare, eventually making up six separate branches. The Connacht O'Connors are the most prominent – they did produce several Kings after all.

O'Neill: The name Neill comes from the word 'niadh' which means 'champion'. O'Neills are descendants of Niall Glundubh (Glundubh meaning 'black knee') who was an old Irish monarch, and the legendary Niall of the Nine Hostages, a High King of Ireland from the 4th century. Legends state that he conquered all of Ireland, Scotland and much of England and Wales during his rule, and took a hostage from each kingdom (hence the name). There were two main strains of the family; in Ulster and in county Meath.

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