A Letter from Ireland:

The Surname O’Neill


Irish Surname O'NeillMary O’Neill Leidner contacted us with a request for more information on the O’Neills (and a story of her own – which you can see at the end of this post).

Meaning of the name O’Neill.

O’Neill (or Neal, Neil, Nihil etc.) comes from the Irish Ó Néill – literally translated as “of Niall”. The main family of the O’Neills – dominant in Ulster for hundreds of years up to the 1600s were from around modern county Tyrone (the chief family of Cinel Eoghan) and descended from “Niall of the nine hostages” (but they took their name from a later Niall who was King of Ireland in the 10th century).

Home Counties of the O’Neills.

Niall, however, was quite a common first name – and a number of septs have sprung up around the country – some related to the Tyrone O’Neills and some not. They were found in counties Antrim, Down, Waterford, Tipperary and Carlow.

Today the name can be found in many places in Ireland in quantity – but is specially found in the Counties of Antrim and Tyrone.

O’Neill Family Castles.

The O’Neill family of Ulster have about sixteen castles in Ireland associated with their family.

Mary’s Family Story:

My great grandfather was Thomas O’Neill, born in Dublin in 1810, He was married to Brigette Delaney.I don’t know when or where she was born. Thomas O’Neill Died in Savage, Howard County, Maryland USA in 1895. We dont know how or when he emigrated. That is all I know of him.

His Son ( my Grandfather )William James O’Neill was born in 1862. I don’t know where and died Dec. 1920 in Oakland, Howard County Md.The story we were told as Children was that our grandfather came to the US from Ireland via Copenhagen met my grandmother Katherine E. French who was also Irish. ( He often told my father that Katherine was of Irish royalty. Although that was a fabrication because we now know that she was born in the US.)

 We are curious to know if William James was born in Ireland and where and how he came to this country.  We think William James had several brothers John, Louis and a sister Theresa . We would love to separate the fact from the fiction.
Mary O’Neill Leidner
Well Mary – let’s see how the story continues below in the comments – but for now, thats the bigger story about the mighty O’Neill families of Ireland!
If you would like to add what you know about the O’Neill surname, tell the story of your O’Neill family OR ask a question – please do so below in the comments section.
Remember – at Your Irish Heritage we consider an “Irish Surname” to be one that belongs in your family. It may belong to an ancestor who lived in Ireland at one stage. We consider old Gaelic, Viking, Norman and planter names to be all Irish – if they fit this criteria.


  • PolecatMtn says:

    I had a DNA test done a few years back. It appears that I match Niall of the Nine Hostages in 12 out of 20 DNA points. I understand that this is not unusual. It seems that I am descended from old Niall by about 20 generations or so. Any other “cousins” out there?

    • Mike says:

      Lots! There is a fascinating book called “The Origins of the Irish” and its thought that up to 25% of all Gaels come from Niall. However, the O’Neills are named after a later Niall! Mike.

  • Mary O'Neill Leidner says:

    Than you Mike for all your very intereting history of Ireland and her people. My O’Neill Ancestors came from Dublin to the US but I think they originally lived in the west of Ireland according to stories told us by me Grandmother Katherine French O’Neill. We were told that our grandmother was related to a Lord French who supposedly came from the Western part of Ireland. It is very difficult to separate the fact from the fiction when it comes to long lost ancestors as the Irishmen who told us the stories truly had the gift of gab. All were great story tellers and we loved them and have fond memories of them. Thank you for this wonderful site.

    • Mike says:

      Thanks for the feedback Mary. The surname O’Neill is on of the more common throughout Ireland. It arose from a number of seperate clans (the most famous being the O’Neils of Tyrone). The largest groups were in Tyrone/Antrim/Down – then Carlow – then Waterford/Tipperary. There are also a few in West Cork and Kerry.

      Interesting about Connaught – there were a group in County Mayo of MacNeills (a Scottish Gallowglass family).

      Thanks for sharing your story! Mike.

      • Gene O'Neill says:

        My family is from eastern Mayo. Does that mean possibly of the Scottish Clan McNeill?

        • Mike says:

          Hi Gene – yes it could be – a Gallowglass (mercenary) group from Scotland settled in Mayo – the MacNeills. But I do notice that your surname is O’Neill which is a different family.Mike.

      • gerry mc dermott (@gerrymac6511) says:

        A lot of Ulster names can be found in west Cork/Kerry this could stem from the battle of Kinsale,when a huge army from Ulster led by O Neill went south to meet the French,in the confusion that followed,quite a few seemed to have stayed on and settled there.

        • Mike says:

          Thats tru Gerry – but in the case of O’Neill, Niall was a common first name and a number of different O’Neill septs sprung up around the country when the surname system came into place. Mike.

      • Mall says:

        A lot of the O’Neills from co. Armagh were driven out of the area during Cromwells mid 17th century campaign and settled in Mayo. Glasdrummond in South Armagh is where the majority of the Mayo oneills come from

  • Maureen O'Neill-Irvine says:

    I am the daughter of Paul Hugh O’Neill of Chicago Illinois. He was married to my mother Mary Lyn Thaler in 1954 the had four children at the time of his passing in December 1958. My father was one of 12 children born on the south side of Chicago… I a trying to find out more information. sincerely Maureen

    • Mike says:

      Hi Maureen – thanks for the enquiry. Unfortunately, I only deal with the bigger picture and cannot help with specific person enquiries. There are a number of geneaology sites out there that should help however! Mike.

  • Johnhorse says:

    I have been trying to find out more about my mothers side of the family.I knew my grand father Edward O’Neil and he passed around 1982 he was born in 1892.I’m sorry I never thought to ask him about his father who came to the U.S.around 188o from Ireland.But now I’m trying to find out more about the O’Neil side.The one thing I do remember is that Great Grand Dad O’Neil was on his way west in the 1880’s in a wagon train and in the Oklahoma territory met and Married my Great Grand mother who was from the Osage Tribe of North East Oklahoma her maiden name was Whitehorse.Now I’m still looking for more info.

    • Mike says:

      Hi there – O’Neill is a name that can come from different parts of Ireland – but the most famous from around County Tyrone. Do join up our weekly newsletter – “Letter from Ireland” at http://eepurl.com/xPw4P where we share lots of information on names such as your own and the places they come from. Mike.

  • Janet Williams says:

    My maternal grandmother was Honora O’Neil. We still have family in County Cork and I have had the pleasure of meeting some of them. I dearly love Ireland. My question is this : Are the O’Neils and the O’Neills two different clans, or were we one and then split off and changed the spelling?

    • Sally O'Neill Mauldin says:

      We may be kin. My Grandfather, Jeremiah O’Neill immigrated from County Cork after the Copper Mine failed there – I think around 1860-1870 – and moved to Houghton, Michigan and then Butte, Montana. I remember the name Honora but will have to do some research to find how she fits.

      • Laura Short says:

        I’m looking for a Jeremiah O’Neill (1832-), also from County Cork, married to a Mary O’Mahoney (1848-) from Basingstoke, Hampshire, England. I’ve not found evidence that this Jeremiah emigrated to the States, although at least three of his sons did: James Joseph O’Neill (1874-1953), Cornelius O’Neill (1882-1954), and Dennis O’Neill. Any hints, greatly appreciated!

  • Carol Staples says:

    I have found a cemetery in Norton Va. call Oneill cemetery. When did the Oneill family drop the O and when by just Neil or Neal. and why?

  • Sara Neill Hodges says:

    My grandfathers, great-grandfather was Benjamin (O’Neill) Neill. He rode the railroad as far west as it went at the time and was one of the first settlers of Miltonvale Kansas. I am from his eldest son James’ line.

    Benjamin was born on Aug 10, 1820 in MAGHARALAGGAN, COUNTY DOWN, Ireland. All I can find is that this is a general area south of Belfast. Do you have a more specific location of Magharalaggan? Also, is it common to have the names listed as just Neill without the O’ , does that have any significance? I don’t know if my line ever had an O or when it lost it.

    Thank you so much for any answers you can provide!

  • Mike Woodcroft says:

    Hello all.

    I no longer have contact with immediate family, however I’m interested in learning about my mothers side of the family.

    My grandfather and grandmother have passed away now. They did come from County Mayo I do believe.

    My grandmother also informed me many years ago, that I am related to James Sloyan, the actor. He is apparently my second cousin, twice removed.

    I’m interested in tracing family history for some reason of late.

    Anyway, I guess that I should start with the names of my grandfather and grandmother.

    Tommy O’Neill who also used the stage name of Gavin O’Grady I am told.

    Mairead O’Neill, was my grandmother who was a nurse and moved to London many years ago.

    Other than that, I don’t really know anything.

    Wishing you all the best.

  • my side of the family, we believe, that they originated in County Donegal. Is what we are told. We spell our name O’Neil.

  • Am interested in O’Neil history to add to
    my geneology.

  • Mall says:

    Hi all,
    Probably late here for any correspondence now! My great grandfather Edward O’NEILL married a Ellen Crimmins from twopothouse co. Cork close to Mallow prob in 1880’s , I have plenty of info on Ellen, but have very little on Edward, I don’t believe he was from cork but was stationed there in military
    Any information would be greatly appreciated.
    Their family moved to Belfast 1890’s, my grandfather John had two brothers that I know of , Patrick & william

    • Barron says:

      I have lots of info on an Edward O’neill, born Feb 21, 1892, but he married a Frances McNally, not Crimmins. I could have the wrong Edward. The only info I have on McNally is that her burial was in Maine, not even any birth, death, or marraige date.

      • Gary says:

        Hi my grandfather was John McBarron from Ulster Ireland, I’ve noticed your a Barron you maybe able to help me what is the connection between the O’Neills and the Barrons I’ve read they were a branch of the O’Neills any info would be great
        Kind Regards

    • Mall says:

      The Edward I was enquiring about had a son called Edward ( of which I have no information what so ever) along with john, patrick , William and a Christopher who died young prob 1904 ish, sisters Ellen , Pauline.
      in 1901 census they are living in Belfast The Mother Ellen and children, no mention of the father Edward.

  • Ellenmarie says:

    I just found my Great great grandmother was Ellen O’Neill (Cashman). Her parents were Peter and Ellen and she was baptized in Enniskerry in County Wicklow in 1830. I was thrilled to find them, as this family line left little information but my eyes have gone batty looking at census!!

  • George says:

    Looking for my great grandfather Patrick O’Neill. His parents were Louis O’Neill and Bridget McIlroy. I do not know where they were from but my Ancestry DNA matches most closely to Northern Ireland.

  • John O'Neal says:

    How can I get info on these 16 O’Neill castles? All I can find is Dungannon and Edenduffcarrig and Henry Avery’s Castle. That leaves thirteen castles unnamed and unaccounted for.
    I have tried every search term I can think of and all that comes up is Dungannon and Shane’s/Edenduffcarrig and sometimes Henry Avery’s and the supposes site of the Gray Castle/ Eagle’s Nest in County Down.

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