O'Dubhagain
Surnames of Meath
[Meath]
O'Maolseachlainn
O hAirt, O'Riagain, O'Ceallaigh, O'Conghalaigh
O'Ruaidhri, O'Fallamhain
O'Coindealbhain, O'Braoin
O'hAneghusa, O'hAedha
O'Dubhain, O'hAinbheith
O'Cathasaigh, O'Leochain
O'Donnchadha, O hIonradhain
O'Maolmhuaidh
O'Dubhlaidhe, O'Fionnallain
O'Maollughdhach, Mag Cochlain
O'Tolairg
Clann-Eochagain, Cinel-Fiachach
Mag Ruairc, O'Cairbre
O'hEochadha, O'Maelcallann
[Teathbha (Teffia)]
O'Catharnaigh, Mag Cuinn, O'Confiacla
O'Lachtnain, O'Muireagain
O'Flannagain, O'Braein
Mac Conmeadha, Mag Aedha
MacTaidhg, Mag Amhalghadha
MagCarrghamhna
O'Dalaigh, O'Muireadhaigh
O'Scolaidhe, O'Comhraidhe
O hAedha, O'Cearbhail
O'Duinn
MacGillaseachlainn, O'Ronain
O'hAenghusa
MacGilla-Mocholmog, O'Dunchadha
O'Muirchertaigh
O'Modhairn
[Ulster]
Kingdom of Aileach - Surnames
Oirghialla - Surnames
The Croabh Ruadh (Red Branch)- Surnames
Cinel Conaill (Tirconnell) - Surnames
[Cenel Eoghainn]
O'Neill, MacLachlain
O'Cathain, O'Conchobair
O'Duibhdhiorma
O hOgain (2)
O’Gairmleadhaigh
O’Ferghail, O’Domhnallain, O’Donnagain, MacMurchada
MacDuinnchuain, MacRuaidhri
O’Ciarain
O’Maoilbreasail, Baoighill, O'Cuinn, O'Cionaith
O'Domhnaill
O'Duibhduannas, O hAghmaills, O hEitigeins
O'Maolfothartaigh, O hEodhusas, O hOgains
O'Bruadair, O'Maoilfabhaill, O'Coinne, O hOgain
O'Murchadha, O'Mellain
O'Fiachra
[Airgialla]
OIRGHIALLA HERE
O'Cearbhaill, O'Duibhdara
MacMathghamnas, Maguidhir
O'Lairgnen, O'Flaithri
O'Flainn, O'Domhnallain, O hEirc
O'Criodain, O hAedha
O'Caomhain, O'Mochoidhein
O hIr, O hAnlauin, O'Cosgraigh
O hInnreachtaigh, MacDomhnaill
Mac Tighernain, O'Flannagain
Mac Giolla Finnen
Mac Gillemichils
Ui hEignigh
Mac Cionaith
O'Corbmaic, O'Gairbhiths
O'Longain, O'Duibheamhna, O'Conchobhair
Ui Lorcain, OhEignigh
O'Domhnaills
O'Lachtnain, O hAinbhith
Mag Uidhir
O'Colgan, O'Conaill
Craebh Ruadh
The Craebh Ruadh
O'Duinnsleibhe, O hEachadha
O hAidith, O hEochagain, O'Labhradha, O'Leathlobhra
O'Loingsigh, O'Morna, O'Mathghamhna
O'Coinne, O'Gairbhith
O hAinbhith
Mag Aenghusa
MacArtain
Mag Dubheamhna ,O'Mornha
Mag Duilechain, O'Coltarain
O'Labhradha
[Cenel Conaill]
Tir Chonaill
O'Maoildoraidh, O'Canannain
O'Baoighill
O'Maoilmaghna, O hAedha
O'Tairchert, Mac Dubhain
Mag Loingseachain, O'Breislen
O'Dochartaigh
MacGillatsamhais, O'Furadhrain
O'Cearnachan
O'Donnagain, MacGaibhidh
O'Maoilgaoithe
MacTighearnain
[Connacht]
Connaught Surnames
Breifne Surnames
Ui-Maine Surnames
Clann-Conchobhair (O'Conor)
Ui-Ruairc
O'Flannagain, O'Maoilmordha, O'Carthaigh, O'Mughroin
O'Maoilbhrennainn
O'Cathalain, O'Maenaigh
Mag Oireachtaigh, O'Finachta
O'Finachta
O'Conceanainn
Mag Murchadha
MacDiarmada
[Breiffne]
O'Ruairc
MacTighearnain
Mac Samhradhain, Mac Consnamha
McCagadhain, Mag Dorchaidh
O'Finn, O'Cearbhaill, Mag Flannchadha
O'Raghallaigh
O'Cuinn, Mac Maoiliosa
Mag-Finnbhairr, Mag-Raghnaill
O'Cuinn
O'Maoilcluiche
O hEaghra, O hUathmharain
O'Gadhra
O'Dobhailen, O'Duinncathaigh
Mag-Eoch, Mag-Maonaigh, Mag Riabhaigh
[Ui-Fiachrach]
O'Dubhda
O'Muireadhaigh, O'Gormog, O'Tighearnaigh
O'Mannachain
O'Maoilmhichil
O hAinlighe
Mac Ceithearnaigh
O'Maoilmuaidh, O'Floinn
O'Rothlain
Mac Sgaithghil, O'Braoin
Ui-Maille
O'Talcharain, O'Cadhla
Mac Conroi, O'hAdhnaidh
Mac Aodha
Mac Gilla Ceallaigh, Ui Eidhin
Ui Cleirigh, Ui Duibhghiolla
O'Maghna, O'Seachnasaigh
[Ui-Maine]
O'Conaill
O'Neachtain, O'Maolalaidh
O'Cathail, O'Mudhroin, O'Maoilruanaidh
Ui Laodhogs
O'h-Uallachain
Mac Eitteagain
Mac Giolla Fionnagain
Ui Domhnallain
O'Donnchadha, Ui Cormaic
O'Duibhginn
O'Docomhlain, O'Gabhrain
O'Maoilbrighde
[Leinster]
Surnames of Leinster
Surnames of Osraighe
Mac Murchadha
O'Fiachrach, O'Cosgraigh
O'Riain, O'Tuathail
Mac Gormain
[Ui Failghe]
O'Brogarbhain, Clann Conchbhair (O'Conor Failghe), O'Duinn, O'Diomasaigh
O'Aenghusa, O'Aimergin, Clann-Murchadhain
O'Ciardha
[Osraighe]
Clann Cearbhaill, Clann Donnchadha
Mac Giollaphatraic
Ui-Bruadair, Mac Braoins
Ui Eirc
O'Huidhrin
[Leinster]
Mac Murchadha
O'Conchobhair
Ui Riagain, O'Duinn
O'hAenghusa
O'Maoilchein
O'hAimirgin
O'Murchain
O'Diomosaigh
O'Ceallaigh
O'Mordha
O'Duibh
O'Ceallaigh
O'Ceallaigh
O'Caollaidhe
O'Gormain
O'Tuathail
Mac Giolla Mocholmog
O'Cosgraigh
O'Gealbrain
O'Taidhg, Ui-Mail, O'Ceallaigh
O'Ciardha
O'Fiachra, O h-Aodha
O'Muirte, O'Finntighearn
O'Murchadha
O'Gairbhidh
O'Duibhginn
O'Lorcain
O'h-Artghoile
O'Riaghain
O'Nuallain, O'Neill
O'Gaoithin, O'Dulaing
[Osraighe]
Mac Giollaphatraic
O'Dubhshlaine
O'Cearbhaill, O'Donnchadha
O'Donnchadha
O'Cearbhaill
O'Braonain
Mac Braoin, O'Broithe
O'Faolain
O'Caibhdeanaigh, O'hCathasaigh
O'Gloiairn
O'Caollaidhe
O'Bruadair
[Munster]
Cashell
Brian (O'Briain)
Mac Carthaigh
O'Donnchadha
O'Deaghaidh, O h-Oilella, O'Brachain
O'Bric, O'Faelain
O'Mearadhaigh, O'Neill
O'Flannagan,
O'Breslin
O'Foghladhas, O'Cein
O'Bric
O'Dubhagain, O'Caoimh
O Anamchadhas
Ui Breaghdha, O'Glaisin
O'Cuirre
O'Ceallachain
O'Mathghamhna
O'h-Eidirsceoil
O'Floinn
O'Cobhthaigh
O'Baire
O'h-Eidirsceoil
O'Domhnaill
O'Donnchadha
O'Ceithearnaigh, Ui-Floinn
O'Bece
O'Mathghamhna
O'Muircheartaigh, O'h-Imhasbhain
O'Seagha, O'Failbhe
O'Conghaile
O'Failbhe, O'Seagha
O'Floinn, O'Maolfabhaill
O hAodha
O'Donnagain
O'h-Ionmhainen
O'Cuirc, O'Maoilbloghain
O'Carthaigh
O'Donghalaigh, O'Fuirg
O'Baiscinn
O'Maolcorcra
O'Ceallaigh
O'Conchobhair
O'Laoghain, O'Caithneannaigh
O'Duibhduin
O'Neidhe
O'Maoileitigh
O'Draighnen
O'Conchobhair
O'Lochlainn
O'Dunadhaigh
O'Donnchadha, O'Cearbhaill
O'Caoimh
O'Ceallachain
Mac Amhlaoibh
O'Tedgamhna
O'Coilen
O'Billraidhe
Mac Innerigh
O'Brearga, O'Maolcallann
O'Cleirchin
O'Donnabhain
O'Ciarmhaic
O'Suilleabhain
O'Cuile, O'Caollaighe
O'Duineachair
O'Merghda
O'Cinnfhaeladh
O'Conaing
O'Luain
O'Deadhaigh
O'Cuinn
O'Cathail
O'Maoilmeadha
Ui Corbmaic, O'h Aichir
Ui-Aichir, Ui Flannchadha
O'Duibhginn
O'Grada
Mac Conmara
O'Dobharchon
O'Neill
O'Echthighern
O'Seanchain
O'Cinneidigh
Muintir-Duibhraic
Ui Toirdhealbhaigh
O'Cadhla, O'Maille
O'Duibhidhirs
O'Cedhadha
O'Conaing
Mag Ceoch, Muintir Loinsigh
O'h-Ifearnain, O'Cathalain
O'Donnagain
Mag-Longachain
Muintir-Duibhidhir
Muintir-Cearbhaill
O'Flannagain
Mag Corcrain
O'h-Aedhagain
O'Dubhlaighe
Mag Gillaphoil
O'Banain
Meachair
O'Ailche
O'Cathail
O'Fogarta
O'Aimrit
Ui Cerc, Ui Maoiluidhir
O'Spealain
Footnotes - O'Dubhagain
Footnotes - O'Huidhrin