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Family Surnames

Do You Have Irish Genealogy? Use This Handy Surname Guide to Trace Your Heritage

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There are tens of millions of Americans with Irish heritage, and many of them still bear those original Irish surnames with pride. But, where did these surnames originate? More importantly, why does it matter? It matters because knowing how your Irish surname evolved can not only tell you important details about your ancient Irish ancestors, it can actually help you trace your family tree in Ireland. If you have an Irish surname, this handy guide to the origins of surnames in Ireland will be a blessing for your family history research.

In very ancient times, people in Ireland didn’t use surnames, because they were not necessary. Most people lived in small villages where everyone knew everyone else, and most residents were related, so it was not necessary to have a surname to distinguish one person or one family from another. As towns grew larger, and there was more migration between them, people began referring to themselves as the “son of” or “daughter of” their father or mother, as the people they encountered probably knew their parents.

Some common prefixes for Irish surnames, such as O’, Mc, and Mac all mean “son of,” and the less common prefix “Ni” means “daughter of.” Interestingly, the word “surname” means “sired by.” The first names of these parents had meanings, too. If your surname is, for example, McAllen, then someone deep in your Irish family tree was named Allen, which is Irish for “handsome.” Before surnames, first names were used to describe the people who bore them.

Usually, a person using a “son of” or “daughter of” word as a surname would have a different first name than their parent, though this was not always true. There were people called “Brian O’Brian,” which essentially means “Brian, Jr.” You can follow a family pretty far back into Irish history using this method of creating surnames.

In fact, the very first recorded instance of an Irish person using a surname (they probably used them earlier, but this is the earliest recorded instance of it) was in 916 A.D. in Galway. The user of the surname was a Lord who called himself Tigherneach Ua Cleirigh. The “Ua” later became the modern O’. This Lord’s descendants are the modern day O’Clery and O’Cleary families.

When the Normans invaded Ireland in 1169, many Irish families using an O’, Mc, or Mac surname changed it to the Latin version of “son of,” which was Fitz, as this is what the Normans used. Other families kept their Gaelic surnames in spite of their oppression by the Normans.

Of course, a person’s parents did not always determine their surname in Ireland. Their occupations were also an extraordinarily common choice of surname. Using an occupation as a surname was the ancient equivalent of giving someone their business card. It was a shrewd business move, and it was easy to do, so it became popular once surnames began to be used in Ireland. A baker, cooper, fisher, butler, thatcher, mason, smith, and wright all had ready surnames in their occupations, and we still find these names are plentiful not only in Ireland but all over the world today.

Less common, but also sometimes used, were geographical surnames. These denoted from where a person (or their family) originated. Someone who came from Bray would use that as a surname. A person from Wales may use Welsh or Walsh as a surname. Geographical features would also be used in surnames, especially in areas where people would know that feature. A person who lived on or near a hill may use “Hill” as a surname. Those who lived on or near mountains, dales, valleys, and rivers would use or incorporate those features into their surnames, as well. River or Rivers are obvious examples. There is also Montgomery (“Mont,” or mountain) and Mondale (“Dale”).

These are how the typical Irish surnames were invented and designated until the 1500’s when the new Protestant religion from England suppressed traditional Irish Catholicism. Protestants from England were given Irish lands and moved there, making the Irish second-class citizens in their own country. To adapt to their new circumstances, many Irish families Anglicized their surnames, allowing them to fit in with their new English neighbors.

In Anglicizing their surnames, names like O’Ceallaigh became Kelly, O’Murchadha became Murphy, and MacGabhann became Smith. The Irish found that their new English neighbors, who were usually their bosses and landlords, could pronounce Anglicized surnames better than traditional Gaelic ones.

As you can see, knowing the history of Irish surnames allows you to more easily follow one generation to the next, going farther back in time on your Irish family tree. It also gives you some insight into who your ancient Irish ancestors were, who their family was, what they did, and where they lived. Irish surnames tell an entire oral history of Irish families going deep into ancient times. While there may not be paper records to show you exactly how each generation connects into the one before it, knowing the surname and the history of it will allow you to fill in some of the important blanks, and to know more about your Irish family than you would with the scanty Irish records alone.

Irish surnames followed the same pattern of most surnames in the world, beginning with referring to oneself as the son or daughter of their father or mother. This was the most common type of surname, and usually, the first one developed when a nation began to adopt them, followed by occupations and geographical features. However, the Anglicized versions of Irish names are unique to Ireland. With a little bit of knowledge about Gaelic, you should be able to determine whether your Irish surname was Anglicized, and you might even be able to trace it back far enough to determine when it was done. From there, you can trace the family back even farther using the original Gaelic surname.