| 1. Murphy |
2. Kelly |
3. O'Sullivan |
4. Walsh |
5. Smith |
6. O'Brien |
7. Byrne |
8. Ryan |
9. O'Conner |
10. O'Neill |
| 11. O'Reilly |
12. Doyle |
13. McCarthy |
14. Gallagher |
15. O'doherty |
16. Kennedy |
17. Lynch |
18. Murray |
19. Quinn |
20. Moore |
| 21. McLaughlin |
22. O'Carroll |
23. Connolly |
24. Daly |
25. O'Connell |
26. Wilson |
27. Dunne |
28. Brennan |
29. Burke |
30. Collins |
| 31. Campbell |
32. Clarke |
33. Johnson |
34. Hughes |
35. O'Farrell |
36. Fitzgerald |
37. Brown |
38. Martin |
39. Maguire |
40. Nolan |
| 41. Flynn |
42. Thomson |
43. O'Callaghan |
44. O'Donnell |
45. Duffy |
46. O'Mahony |
47. Boyle |
48. Healy |
49. O'Shea |
50. White |
| 51. Sweeney |
52. Hayes |
53. Kavanagh |
54. Power |
55. McGrath |
56. Moran |
57. Brady |
58. Stewart |
59. Casey |
60. Foley |
| 61. Fitzpatrick |
62. O'Leary |
63. MacDonnell |
64. MacMahon |
65. Donnelly |
66. Regan |
67. Donovan |
68. Burns |
69. Flanagan |
70. Mullan |
| 71. Barry |
72. Kane |
73. Robinson |
74. Cunningham |
75. Griffin |
76. Kenny |
77. Sheehan |
78. Ward |
79. Whelan |
80. Lyons |
| 81. Reid |
82. Graham |
83. Higgin |
84. Cullen |
85. Keane |
86. King |
87. Maher |
88. MacKenna |
89. Bell |
90. Sco |
| 91. Hogan |
92. O'Keefe |
93. Magee |
94. Mullan |
95. MacDonald |
96. MacDermot |
97. Moloney |
98. O'Rourke |
99. Buckley |
100. O'Dwyer |
|
Gaelic Name - Anglicized name -
Early County Origin - Other Roots
from: Mac an Bhreitheamhan - (Mac) Abraham,
Abrehan, Judge - Co Cork
Ó hEachthianna - Ahern or Hearne
- Co Clare - the Dal gCais (e.g. Brian Boru)
Mac an tSaoir - MacAteer - Ulster,
(St. Ciaran)
Mac Amhalghaidh - MacAuley or MacAwley
- Co Offaly/Westmeath, lords of Calry
Mac Amhlaoibh - MacAuley or MacAwley
- Co Fermanagh - branch of MaGuire
Mac Amhlaoibh - MacAuliffe - Co
Cork - branch of MacCarthy
Mac Árdghail - MacArdle -
County Monaghan, Armagh and Louth of Oriell
Ó Banain - O Bannion - Co
Fermanagh
Ó Beaglaoich - Begley - Co
Donegal
Ó Birn - (O) Beirne - Co
Roscommon - chiefs of Tir Briuin
Ó hAimheirgin - (O) Bergin
- Co Offaly - chiefs of Geashill
Ó Beolláin - (O) Boland
- Co Sligo - Uí Fiachrach
Ó Beolláin - (O) Boland
- Co Clare - Dalcassian
Ó Baoghill - (O) Boyle -
Co Donegal
Ó Baoighealláin - (O)
Boylan - Fermanagh/Monaghan - same stock as O'Flanagans
Mac Bradaigh - Brady - Co Cavan
Ó Brollacháin - (O) Brallaghan
or Bradley - Co Tyrone/Derry - Cinel Feradaigh
Mac Braoin - (Mac) Breen - Ossory,
Co Kilkenny
Ó Braoin - (O) Breen - Westmeath/Offaly
- Lord of Brawney
Mac an Bhreitheamhnaigh - (Mac) Breheny,
Judge - Co Sligo/n. Roscommon
Mac Branain - MacBrennan - Co Roscommon
- chiefs of Corca Achlann
Ó Braonain - (O) Brennan
- Co Kilkenny, East Galway, Westmeath and Kerry
Ó Breislein - (O) Breslin
- Co Donegal, Cenel Enda, chiefs of Fanad
Ó Bric - (O) Brick - Co Waterford
- of the Decies
Ó Bruic - (O) Brick - Co
Kerry - originally of Thomond
Mac Giolla Bhride - MacBride or Kilbride
- Co Donegal
Ó Briain - O'Brien - Munster
(Thomond) - the Uí Toirdealbhaigh, part of the Dal gCais
Ó Bruadiar - (O) Broder or Broderick
- Co Cork, Limerick and Galway
Ó Brógáin - (O)
Brogan - Co Mayo - the Uí Fiachrach
Ó Brolaigh - (O) Brolly, Brally,
Brawley - Co Donegal/Derry - Cinel Oenghusa
Ó Bróithe - (O) Brophy
- Co Kilkenny, Laois
Ó Brosnacháin - (O) Brosnan
- Co Kerry
Ó Buachalla - Buckley - Co
Tipperary/Offaly
Ó Bogaigh - Buggy - Co Kilkenny/Wexford
(origin unknown)
Mac Conboirne - Burns
- N. Connaught - mainly of Scottish origin
Ó Broin - (O) Byrne, Burns - Co Kildare/Wicklow - Uí Broin sept
of Crioch Branach
Mac Gafraidh - (Mac) Caffrey - Co
Tyrone/Fermanagh - branch of the Maguires
Ó Cathain - O'Cahan or Kane
- East Donegal - Cenel Eoghain
Ó Cathail - (O) Cahill -
Co Galway - chief of Kinelea
Ó Cathail - (O) Cahill -
Co Kerry and also in Tipperary
Ó Ceallacháin - (O) Callaghan
- Co Cork - the Eoghanacht, descent from Ceallachan
Ó Cathaláin - (O) Callan
- Co Monaghan/Louth - named from a king of Fernmag.
Mac Cathmhaoil - Campbell - Co Tyrone - Cenel Fearadhaigh
Theas of Cenel Eoghain
Mac Cailein - Campbell - Co Donegal
- Scottish gallowglass of Cenel Eoghain
Ó Ceanndubháin - (O) Canavan
- Co Galway, physicians to O'Flaherty of Connemara
Mac Cuindlis - MacCandless - Co
Down
Mac Anna or Canna- MacCann - Co
Armagh - lords of Clanbrassil (Cenel Eoghain)
Ó Canain - (O) Cannon - Co
Galway - the Uí Maine, same stock as O'Madden
Ó Canannain - (O) Cannon
- Co Donegal - Kings of Cinel Conaill (pre-1200)
Ó Caithniadh - (O) Canny
- Co Mayo - Uí Fiachrach Muaidhe, chiefs of Erris
Ó an Cháintigh - (O) Canty
- west Co Cork
Ó Cairbre - (O) Carbery -
Co Westmeath - chiefs in Clonlonan
Ó Ciardha - (O) Carey - Co
Kildare - southern Uí Neill, lords of Carbury
Ó Cearmada - (O) Carmody
- east Co Clare
Mac Cearnaigh - (Mac) Carney or Kearney
- Co Meath and Monaghan/Armagh
Ó Cearrnaigh - (O) Carney
- Co Mayo - Uí Fiachrach
Ó Cairealláin - (O) Carolan
- Co Derry - chief of Clan Diarmada
Ó Cearbhalláin - (O) Carolan
- Co Cavan/Monaghan
Ó Cairre - (O) Carr and (O) Carry
- various, e.g. of Cenel Aengusa
Ó Cearbhaill - (O) Carroll
- Co Offaly and Tipperary - lords of Eile (Ely)
Ó Cearbhaill - (O) Carroll
- Co Monaghan and Louth - chiefs of Oriel
Ó Cearbhaill - (O) Carroll
- Co Leitrim/Sligo - chief of Calraighe
Ó Cearbhaill - (O) Carroll
- Co Kilkenny - chief of northern Gowran
Ó Cearbhaill - (O) Carroll
- Co Kerry - chief of Locha Lein
Mac Cearbhaill - (Mac) Carroll or MacCarvill
- Ulster
Mac Artian - MacCartan - Co Down
- chiefs of Kinelarty
Mac Carthaigh - MacCarthy - Munster
(Tipperary) - the Eoghanacht
* MacCarthy Mor - South Kerry
* Dunhallow MacCarthys - Northwest Cork
* MacCarthy Riabhach - Carberry, Southwest
Cork
* MacCarthy Muskerry - Cork/Kerry border
Ó Cathasaigh - (O) Casey
- various, including lords of Suaithni (co. Dublin)
Mac Cathasaigh - MacCasey or Casey
- Co Louth/Monaghan
Ó Caiside - Cassidy - Co
Fermanagh
Mac Fhlannchaidh - (Mac) Clancy
- Co Clare - Dal gCais, branch of MacNamara
Mac Fhlannchaidh - (Mac) Clancy
- Co Leitrim - chief of Dartry (Rosclogher)
Ó Cleireigh(Clery) - Clark(e) - Connacht, Donegal - chiefs of Uí
Fiachra Finn
Ó Cléirigh - (O) Clery
or Cleary - Co Galway - Tigherneach Ua Cleirigh, lord of Aidhne
Ó Cleirchín - (O) Clerkin,
Clerk, Cleary - Co Limerick - Uí
Fidhgeinte, Uí-Cairbre
Mac Cluin - (Mac) Clune - Co Clare
Mac Bhloscaidh - McCluskey - Co
Derry - a branch of the O'Cahans
Ó Cobhthaigh - (O) Coffey
- Co Cork - same stock as O'Driscolls
Ó Cobhthaigh - (O) Coffey
- Co Roscommon - Uí Maine branch of the O'Maddens
Ó Cobhthaigh - (O) Coffey
- Co Westmeath
Mac Cagadhain - Cogan - Co Leitrim
Ó Colmáin - Coleman
- Co Sligo, barony of Tireragh - Uí Fiachrach
Ó Clúmháin - Coleman
or O'Colman - Co Sligo/Cork - descendant of Clumhan
Mac Colghain - (Kil) or (Mac) Colgan
- Co Offaly - same stock as O'Dempsey and O'Dunne
Ó Colghain - (O) or (Mac) Colgan
- Co Derry and also of Co Donegal
Ó Coileáin - Collins
- Co Limerick and later West Cork - lords of Connello
Ó Cuilleáin - Collins
- West Cork - Corca Laoidhe
Ó Concheannain - (O) Concannon
- Co Galway - Uí Maine, lords of Uí Diarmada
Ó Caoindealbháin - (O)
Conlan, Quinlan - Co Meath, princes of Uí Laeghari
Ó Connalláin - Conlon,
Conlan or Connellan - Co Galway and Roscommon
Ó Coinghiolláin - Conlon
- Co Sligo
Ó Conaill - O'Connell - Co
Kerry - chief of Magunihy
Mac Dhomhnaill - Connell and MacConnell
- Ulster - the Clan MacDonald
Ó Conghalaigh - (O) Connolly
- Connolly - Co Fermanagh and Monaghan
Ó Coingheallaigh - Connolly
- West Cork
Ó Congalaig - (O) Connolly
- Co Dublin/Meath
Mac Canann - Mac Connon - Co Monaghan
Conchobhair - (O) Connor - Co Offaly
- descent from Cathaoir Mor
* O'Conor Don, Roe, & Sligo - Connacht,
Co Roscommon
* O'Conor Faly - Co Offaly
* O'Conor of Corcomroe - North Clare
* O'Connor Kerry - Co Kerry and also in
Keenaught, Co Derry
Ó Maolconaire - (O) (Mul)Conry
or Conroy - Co Roscommon
Ó Conraoi - (O) Conry or Conroy
- Co Roscommon/Galway - Uí Maine
Mac Conraoi - (Mac) Conroy or King - Co Galway - lord of Delvin of the Two Lakes
Mac Consaidín - MacConsidine
- Co Clare - Dal gCais, a branch of O'Brien
Mac Conmhaoil - MacConville or Conwell
- Co Armagh (Oriel)
Ó Conbhuidhe - (O) Conway
- Co Sligo
Ó Connmhacháin - (O) Conway
- Co Mayo - same stock as O'Hara
Mac Connmhaigh or Connmeadha - (Mac)
Conway - Thomond
Mac Conmidhe - (Mac) Conway or MacNamee
- Co Derry and Tyrone
Mac Congail - Conwell or MacConwell
- Co Down
Ó Cuagain - Coogan - Galway/Roscommon
- the Uí Maine
Mac Giolla Chomhgaill - (Mac) Cool
- Donegal
Mac Cuille or Mac Giolla Chuille - Cooley
- Connacht, Roscommon, Clare, Galway.
Ó Cuana - Cooney - Co Tyrone,
then north Conacht
Ó Culachain - Coolihan or O'Cuolihan
- Co Mayo - the Uí Fiachrach
Mac Corcrain - (Mac) Corcoran -
Co Offaly/Tipperary, chief of Clan Ruainni
Ó Corcráin - (O) Corcoran
- Co Fermanagh
Mac Cormac - MacCormack - various
Ó Corraidh or Ó Corra -
(O) Corr or Corry - Co Tyrone-Fermanagh
Ó Corragáin - (O) Corrigan
- Co Fermanagh - same stock as Maguire
Ó Cosraigh - (O) Cosgrave
- Co Wicklow, later Wexford
Ó Cosraigh - (O) Cosgrave
- Co Galway - Uí Maine
Ó Cosraigh - (O) Cosgrave
- Co Monaghan - chiefs of Fir Rois
Mac Oistoghín - (Mac) Costigan
- Co Laois - a branch of Fitzpatrick
Mac Oitir - (Mac) Cotter - Co Cork
Mac Cochláin - (Mac) Coughlan
- Co Offaly - Dal gCais, chief of Delvin MacCoughlan
Ó Cochláin - (O) Coughlan
- Co Cork
Mac Coibheanaigh - Coveney - Co
Kilkenny (Ossory) - in Crannagh barony
Mac Giolla Chomhgaill - MacIlhoyle or
Coyle - Donegal
Ó Cadhain - Coyne, Kyne or Coen
- Co Mayo - the Uí Fiachrach
Mac Ruidhri - MacCrary or MacCreary
- Unknown - variant of MacRory?
Craobhach - Creagh - Co Clare -
branch of the O'Neills of Clare
Ó Croidheáin - (O) Crean
- Co Donegal/Sligo - Cenel Eoghain
Ó Creacháin - (O) Crehan
- Co Mayo - the Uí Fiachrach
Ó Criocháin - (O) Crehan
or Creighton - Co Tyrone- an Oriel sept
Mac Conchruachan - (Mac)Croghan
- Co Roscommon
Mac Criomhthainn - MacCrohan - Co
Kerry
Ó Croinin - Cronin - Co Cork
Ó Cruadhlaoich - Crowley
- Carbery, Co Cork - Uí Briuin Ai
Ó Cuidighthigh - Cuddihy
- Co Cork and Tipperary
Ó Cathaláin - (O) Culhane
or Cahalane - Co Limerick - chiefs of Owney Beg
Ó Cuilinn - (O) Cullen -
Co Wexford and Wicklow
Ó Cuileannáin - (O) Cullinane
- Co Cork - Corcu Liadhe
Ó Cuileannáin - (O) Cullinan
or Cullen - Co Donegal - of Mullinashee
Ó Coimín - (O) Cummins,
Commons - Co Mayo
Mac Coinín - (Mac) Cunneen
- Co Mayo
Ó Coinín - (O) Cunneen
or Rabbit - Co Offaly and of Thomond
Ó Connagáin and Mac Cuinneagain
- Cunningham - Co Sligo - Uí Fiachra
Ó Connagáin and Mac Cuinneagain
- Cunningham - Galway/Roscommon - Uí Maine
Mac Toirdhealbhaigh - MacCurley, Curley
or Terry - Connacht
Ó Curráin - (O) Curran
- SW Connacht - Uí Maine
Ó Corraidhin - (O) Curreen or
Curren - Co Leitrim
Mac Curtain - (Mac) Curtin - Co
Clare
Mac Cosraigh - MacCusker - Co Tyrone
- ernaghs of Clones
Ó Comhraidhe - (O) Corry and
Curry - Co Clare
Ó Comhraidhe - (O) Curry
- Co Westmeath - chiefs of Moygoish
Ó Dalaigh - (O) Daly - Co
Westmeath - Uí Maine branch of the southern Uí Neill
Ó Dorchaidhe - (O) Darcy
- Co Mayo and Galway - also of Norman origin
Ó Duibhdabhoireann - (O) Davoren
- Co Clare
Ó Deághaidh - (O) Dea
- Co Clare - of Inchiquin
Ó Dulchaointigh - (O) Delahunty
- Co Tipperary/Kilkenny
Ó Dubhshláinte - (O) Delany
- Co Laois
Ó Diomasaigh or Dimmussaig - (O)
Dempsey - Clanmalier between Co Laois and Offaly
Ó Duineachdha - (O) Dennehy or
Denny - Co Cork
Ó Duibhdíorma - (O) Dermond,
Dermott, Darby - chiefs of Breadach in Inishowen
Mac Diarmada - MacDermot - Co Roscommon/Sligo
- of Mag Luirg (Moylurg)
Ó Duibheamhna - (O) Devany
- Co Armagh/Down - ancient chiefs of Ui Breasail
Ó Duibhghiolla - (O) Devilly
- Co Galway - the Uí Fiachrach Aidne
Ó Duibhghiolla - (O) Devilly
- Co Galway - the Síol Anmchadha
Ó Daimhín - (O) Devine
- Co Fermanagh - lord of Tirkennedy
Ó Doibhilin - (O) Devlin
- Co Tyrone and Sligo - lords of Muinter Devlin, Cenel Eoghain
Ó Doibhilin - (O) Devlin
- Co Sligo - chiefs in Corran, standard bearer to O'Connor
Ó Dubhuidhe - (O) Devoy or Deevy
- Co Laois - 7 Septs of Leix, lord of Cremthainn
Ó Duilleain - Dillon - Co
Westmeath, Longford and Mayo - Norman origin
Ó Duinnín - (O) Dinneen,
Dinan - Co Cork - the Corcu Laiodhe
MacDail re Deachair - (Mac) Dockery
- Co Roscommon - Clan Dail re deacair (Sil Murray)
Ó Dubhchonna - Doheny or Downey
- Co Cork - the Corcu Laoidhe
Ó Dochartaigh - Doherty or Dougherty
- Co Donegal - Cenel Conaill, lords of Inishowen
Ó Dubhhláin or Dobhailen
- Dolan - S. Roscommon and E. Galway - the Uí Maine
Ó Domhnallain - Donlan -
S. Galway - the Uí Maine
Mac Donnchadha - MacDonagh - Co
Cork - lords of Duhallow, branch of MacCarthy
Mac Donnchadha - MacDonagh - Co
Sligo - lords of Corran, a MacDermot branch
Ó Donnagáin - (O) Donegan
- Co Cork - of Muscraige Tri Maighe
Ó Donnagáin - (O) Donegan
- Co Westmeath - of Críoch Dungan
Mac Duinnshléibhe - (Mac) Donlevy
or Dunleavy - Co Down (Ulidia)
Mac Domhnaill - MacDonnell - Co
Antrim - of Clan MacDonald (Scotch-Irish)
Mac Domhnaill - MacDonnell - Co
Fermanagh - of Clankelly
Mac Domhnaill - MacDonnell - Clare/Limerick
(Thomond)
Ó Domhnaill - O'Donnell -
Co Donegal - the Northern Uí Neill
Ó Domhnaill - O'Donnell -
west Clare and east Galway - the Uí Maine
Ó Domhnalláin - O'Donnellan
- Co Galway - the Uí Maine, lord of Clan Breasail
Ó Donnghaile - Donnelly -
Co Donegal. later Tyrone - Cinel Eoghain
Ó Donnchadha - (O) Donoghue Mór
- Co Cork, Kerry - Eoghanacht Locha Lein
Ó Donnchadha - (O) Donoghue of
the Glen - Co Cork. Kerry - the Eoghanacht
Ó Donnchadha - (O) Donohoe
- Galway, Cavan and various
Ó Donndubháin - (O) Donovan
- Co Limerick, then SW Cork - chiefs of Carberry
Ó Duacháin - (O) Doohan
- Co Donegal
Ó Duighlaich - (O) Dooley
- Co Westmeath, then NE Tipperary - lords of Fertullagh
Ó Deoráin or O Deoradháin
- (O) Doran - Co Laois - 7 Septs of Leix
Ó Deargáin - (O) Dorgan
- Co Cork
Ó Dudbhchon - (O) Doughan
- Co Cork - Corcu Laoidhe sept
Ó Dubhda - (O) Dowd - Co
Mayo and West Sligo - Uí Fiachrach Muaide
Ó Dunlaing - (O) Dowling
- Co Laois - 7 Septs of Leix
Ó Dúnadhaigh - (O) Downey
- Co Galway - lords of Sil Anmchadha
Ó Dúnadhaigh - (O) Downey
- Cork/Kerry/Limerick border - of Luachair
Ó Dubhghaill - Doyle - Co
Carlow, Wexford and Wicklow (Norse origin?)
Ó hEidirsceoil - (O) Driscoll
- South Kerry, then West Cork - Corca Laoighde
Ó Diubháin - Duane or
Devane - Co Galway - erenaghs of Killursa
Ó Dubhthaigh - (O) Duffy
- Septs from Co Donegal, Roscommon and Monaghan
Ó Dubhagáin - (O) Duggan
- North Cork - Fir Maighe
Ó Dubhagáin - (O) Duggan
- Co Galway - in the territory of the Uí Maine
Ó Diubhgeannáin - (O)
Duigenan, Deignan, Dignam, ... - Co Roscommon, Leitrim - erenaghs of Kilronan
Ó Doinn or Duinn - (O) Dunn or
Dunne - Co Laois - lords of Iregan
Ó Donnchadha - (O) Dunphy
- Co Kilkenny - of Iverk barony
Ó Diubháin - Dwane, Devane
or Duane - Co Meath - of Knowth
Ó Diubháin - Dwane, Devane
or Duane - Co Cork - Corcu Laiodhe
Ó Duibhir or O Dubhuidhir - (O)
Dwyer - West Tipperary - of Kilnamanagh
Mac Aodhagáin - (Mac) Egan
- Uí Maine territory, then Ormond
Mac Giolla Domhaigh - MacEldowney
- Co Derry
Mac Giolla Rua - (Mac) Elroy - Co
Fermanagh
Mac Conchradha - MacEnchroe or Crowe
- Co Clare
Mac Inneirghe - MacEnery - Co Limerick
- Uí Cairbre, same stock as O'Donovan
Ó hAonghuis - Ennis - Co
Offaly and Meath - variant of O'Hennessy
Mac Fhiodhbhuidhe - MacEvoy - Co
Westmeath, Laois - one of the "7 Septs of Leix"
O'Faodhagáin- Fagan - E.
Airgialla (Oriel) - also of Norman origin
Ó Fathaigh - Fahy - Co Galway
- Uí Máine, of Pobal Muintir Uí Fhathaigh
Ó Fallamháin - (O) Fallon
- Co Roscommon - sept of the Uí Máine (Clann Udach)
Ó Fallamháin - (O) Fallon
- Co Meath - of Crich na Cetach
Ó Failbhe - (O) Falvey -
Co Kerry - the Corca Duibhne
Ó Fhearghaill or Fergail - (O)
Farrell - Co Longford - lords of Annaly
Ó Faircheallaigh - (O) Farrelly
or Farley - Co Cavan/Meath
Ó Faracháin - (O) Farren
- Co Donegal - Lord of Finross
Ó Fearáin - (O) Fearon
- Co Armagh (Oriel) - the Cenél Eoghain
Ó Fiannaidhe - (O) Feeney
- Co Sligo/Mayo - sept of the Uí Fiachrach
Ó Fidhne - (O) Feeney - Co
Galway/Roscommon
Ó Fithcheallaigh - (O) Fehilly,
Field - Co Cork - sept of the Corca Laoidhe
Ó Fiachna - - (O) Feighney, Feeheny,
Hunt - Co Roscommon/Sligo - of Síol Muireadhaigh
Ó Fiachra - - (O) Feighry, Feehery,
Hunt - Co Tyrone
Ó Fionnaláin - (O) Fenelon
- Co Westmeath - chiefs of Delvin (Delbna)
Ó Fiangusa - (O) Fennessy
- Co Tipperary/Waterford - chiefs of a district near Cashel
Ó Fearadhaigh - (O) Ferry, Farry
- Co Donegal - Cenél Conaill
Ó Fionnachta - (O) Finaghty,
Finerty - Co Roscommon - of Síol Muireadhaigh
Ó Fionnachta - (O) Finaghty,
Finerty - Co Galway/Roscommon - Uí Maine chiefs of Clanconway
Ó Fionnáin - (O) Finan
- Co Mayo - Uí Fiachrach Muaighe chiefs of Coolcarney
Ó Fionn - (O) Finn - Co Sligo
- chiefs of Calry
Ó Fionn - (O) Finn - Co Galway
- erenaghs of Kilcolgan
Ó Fionn - (O) Finn - Co Monaghan
- of Fir Rois
Ó Fionnagáin - Finnegan
- Roscommon/Galway
Ó Fionnagáin - Finnegan
- Cavan/Monaghan/Louth - a Breifne sept
Ó Finntighearn - Finneran
- Co Westmeath? - chiefs of Uí Mella
Mac Fionbhair - Finnevar - Co Leitrim
- chiefs of Muintir Greadain
Mac Giolla Mo-Cholmog - Fitz Dermot
- Uí Dunchada of Dublin/Kildare
Mac Giolla Phadraig - Fitzpatrick
- lords of Upper Ossory (Laois/Kilkenny)
Ó Flaithbheartach - (O) Flaherty
- Co Galway - Lord of Moycullen and Iar-Chonnacht
Ó Flannagáin - Flanagan
- Roscommon & Offaly
Ó Flannagáin - (O) Flanagan
- Fermanagh - Cenel Cairbre of Tuath Ratha (Toora)
Ó Flannagáin - (O) Flanagan
- Monaghan - Clan Ceallaigh - the MacDonnels of Clankelly
Ó Flannabhra - Flannery -
Co Mayo - the Uí Fiachrach
Ó Flannabhra - Flannery -
Co Limerick - the Uí Fidhgheinte, chief of Dal Cairbri
Ó Flaithre - (O) Flattery
- Co Down - lords of Lecale, kings of Ulidia
Ó Floinn - (O) Flynn - Co
Cork - Muscraige Uí Fhloinn
Ó Floinn - (O) Flynn - Co
Cork - Corcu Laoidhe
Ó Floinn - (O) Flynn - Co
Roscommon
Ó Flainn - (O) Flynn - Co
Antrim
Ó Fhloinn - (O) Lynn - Co
Armagh - Clanna Rury, descent from Coll Uais
Ó Fhógartaigh- Fogarty
- Co Tipperary, Eliogarty - Dalcassian
Ó Foghladha - Foley - Co
Waterford
Mac Giolla na Naomh - Ford - South
Connacht
Mac Conshnámha - Forde or MacKinnawe
- Co Leitrim - chiefs of Muintir Kenny
Ó Fuaráin - Forde or Foran
- Co Cork
Macgiollarnath - Ford - southern
Connemara
Ó or Mac an tSionnaigh - Fox
- Co. Meath - nickname of a chief of Teffia
Ó Firghil - (O) Friel - Co
Donegal - descent from Eoghan, brother of St. Columbcille
Ó Gamhna - Gaffney or Caulfield
- Ossory (Laois/Kilkenny)
Mac Carrghamhna - Gaffney or MacCaron
- Co Cavan and also Roscommon
Mac Conghamhma - Gaffney or Caulfield
- S Galway - Uí Fiachrach Aidhne
Ó Gallchobhair - (O) Gallagher
- Co Donegal - Cenel Conaill
Ó Gealbháin - (O) Galvin
- Co Clare
Ó Gaibhtheacháin - (O)
Gahan - Co Mayo - the Uí Fiachrach Muaide
Mag Fhionnáin - (Mac) Gannon
- Co Mayo
Ó Gadhra - O'Gara - Co Sligo/Roscommon
- chiefs of Luighne Connacht
Mag Fhearadhaigh - (Mac) Garry -
Co Roscommon/Leitrim
Ó Gairbhith - (O) Garvey
- southern Co Armagh, then Down
Ó Gairbhín - (O) Garvey
or Garvin - Co Meath, then Mayo - So. Uí Neill
Ó Garbháin - (O) Garvey
or Garvan - Co Cork/Kerry - same stock as O'Moriarity
Mac Gairbhín - (Mac) Garvey
- Co Donegal
Mag Aodha - MacGee - Co Westmeath
- of Muintir Tlámáin
Mag Aodha - MacGee - Donegal/Tyrone
border
Mag Aodha - MacGee - Also of Scottish
extraction, with Irish origins
Mag Aonghusa - Magennis or (Mac) Guinness
- Co Down - the Dal Araidhe, lords of Iveagh
Mag Eochagáin - (Mac) Geoghegan
- Co Westmeath - so. Uí Neill, chiefs of Kinalea
Mag Oireachtaigh - (Mac) Geraghty
- Co Roscommon/Galway - Uí Briuin Ai (in Uí Maine)
Mac Giolla Phóil - (Mac)Gilfoyle
or Powell - Co Offaly
Mac Giolla Mochuda - MacGillycuddy
- Co Kerry - an O'Sullivan Mór branch
Ó Glaimhin - Glavin - Connacht
- the Hy Fiachrach
Ó Glesáin - Gleeson or
O'Glissane - Tipperary - same stock as O'Donegan
Mag Fhloinn - MacGlinn - Roscommon/Westmeath
Ó Gradaigh - (O) Grady -
Co Clare & Limerick - the Dal gCais
Mac Congail - MacGonigle - Co Donegal
Ó or Mac Gormain - Gorman
- Co Laois - Uí Bairrche
Ó Gairmleadhaigh - (O) Gormley
- Raphoe, Co Donegal - of Cinel Moen (their tribe name)
Mag Shamhradháin - MacGovern
/ Magauran - Co Cavan - descent of Eochaidh (O'Rourke)
Mac Gabhann - MacGowan or Smith - Co Cavan
Ó Grádaigh - (O) Grady
- Co Clare and Limerick
Mac Raith - MacGrath - Co Donegal/Fermanagh
Mac Raith - MacGrath - Co Clare
Ó Griobhtha - Griffin - Co
Kerry and Clare
Mac Carrghamhna. later Ó Gramhna
- (O) Growney - Co Tipperary
MagUiginn or MacGuagáin - MacGuigan
- Co Tyrone - Cenel Eoghain
Mac Aonghasa or Oengussa - (Mac) Guinness
or Magennis - Co Down - the Dal Araidhe
Mag Uidhir - MacGuire or Maguire
- Co Fermanagh - rulers of Fermanagh
Ó hÉidin - Hade, Haide,
Hayde - Co Galway
Ó hAodhagáin - (O) Hagan
or Aiken - Co Tyrone - chiefs at Tullahogue
Mac Céile - MacHale - Co
Mayo - also of Welsh origin
Ó haileacháin - (O) Hallahan
- Co Cork/Waterford
Ó hAileagáin - (O) Halligan
- Co Louth/Armagh (Oriel)
Ó hAllmhuráin - (O) Halloran
- Co Clare (Thomond) - same stock as McNamaras
Ó hAllmhuráin - (O) Halloran
- Co Galway - Chiefs of Clann Fearghaile
Ó hAghmaill - (O) Hamill
- South Tyrone - Cenél Eoghain (Cenél Binnigh)
Ó hÁinle - (O)Hanley or
Hanly - Co Roscommon
Ó hAnluain - (O) Hanlon -
Co Armagh - lords of Orior
Ó hAnrachain - (O)Hanrahan
- Co Clare/Limerick - the Dal gCais
Ó hAnrachtaigh - (O)Hanraghty
or Hanratty - Co Armagh and north Co Louth (Uí Meith)
Ó hEaghra or Egra - O'Hara
- Co Sligo - lords of Luighne with the O'Garas
Ó hÍr - O'Hare - Co
Armagh - Oriel sept of Ó hÉir
Ó hAirt - (O) Hart - Co Meath
- southern Uí Neill, Four Tribes of Tara
Ó hIongardail - Harrington
- Co Cork and Kerry
Ó hArrachtain - Harrington or
O'Harraughton - Co Galway
Ó hArtagáin - (O) Hartigan
- Co Clare/Limerick - the Dal gCais
Ó hEidedín - Hayden or
(O) Headon - Co Carlow
Ó hAodha - Hayes - various
counties
Ó hAodha - (O) Hea - Co Cork,
Corca Laoidhe
Ó hEilidhe - Healey - Co
Sligo
Ó hEaladaighthe - Healey
- Muskerry, Co Cork
Ó hEilidhe - (O) Healy -
Co Sligo
Ó hÉalaighthe - (O) Healy
or Healihy - Co Cork
Ó hÉignigh or O hEicnig -
(O) Heany or MacAnenay - Co Fermanagh - Kings of Fermanagh
Ó hEachighearna - Hearne or Ahern
- Co Clare - the Dal gCais
Ó hEadroman - (O) Hederman, Hetherman,
Heatherman - Co Clare/Limerick, east Cork
Ó hIfearnáin - (O) Heffernan
- Co Clare/Limerick - chiefs of Owneybeg
Ó hEigceartaigh - Hegarty
- Co Donegal & Derry - Cenel Eoghain
Ó hAichir - (O) Hehir or (O)
Hare - Co Clare - Uí Fidhgheinte, lords of Magh Adhair
Ó hAonghusa - Hennessy or Henchy
- Co Offaly - lords of Clan Cholgain
Ó hAonghusa - Hennessy -
Co Dublian/Meath - chief of Gailenga Beg
Ó hAonghusa - Hennessy -
Co Cork - Corca Laoidhe
Ó hInneirghe - Henry or O'Henery
- Co Tyrone - chief of Cullentra
Ó hAiniarriadh - Henry -
Southeast Ulster
Mac Einri - Henry - North Anthrim/Derry
Ó hOireachtaigh - (O) Heraghty
- Co Galway and Mayo
Ó hIcidhe - Hickey - Co Clare
& N. Tipperary - the Dal gCais
Ó hUigín - Higgins
- Co Westmeath, Sligo and Mayo - Southern Uí Neill
Ó hÓgáin - Hogan - Co Clare & Tipperary - the Dal
gCais
Ó hUallacháin - (O) Holohan
- Co Offaly - of Clan Colgan with the O'Hennessy's
Ó hOdhráin - (O) Horan
- Co Galway and Mayo
Ó hUallacháin - Houlihan
- West Munster and Thomond
Mac Aodha or Aoidhe - MacHugh -
West Galway - branch of O'Flahertys
Mac Aodha or Aoidhe - MacHugh -
North Galway
Mac Aodha or Aoidhe - MacHugh -
Co Fermanagh
Ó hAodha - Hughes - Ulster
Ó Urthaile - (O) Hurley -
Co Clare & N. Tipperary - the Dal gCais
Ó hUirthile - (O) Hurley
- West Cork
Ó hIarlatha - (O) Herlihy or
(O)Hurley - Cork
Ó hEidhin - (O) Hynes or (O)Heyne
-Galway - Uí Fiachrach Aidne
Mac Giolla Bháin - MacIlwaine
or Kilbane - Co Sligo - the Uí Fiachrach
Mac Giolla Riabhaigh - MacIlwraith
- Unknown
Mac an Airchinnigh - MacInerney
- Co Clare - son of the erenagh
Ó Cathain - Kane or O'Cahan
- East Donegal/Derry - Cenel Eoghain
Caomhanach - Kavanagh - Wexford
and Carlow - descent from Donal MacMurrough
Ó Cadhla - (O) Kealy - Co
Galway - chiefs of Connemara
Ó Cathain - Keane - Co Galway
(Thomond) - Uí Fiachra Aidne
Ó Cein - Kean - Co Waterford
Ó Cearrnaigh - Kearney -
Co Clare - Dalcassian
Mac Cearnaigh - Kearney - Ulster
- Cenel Eoghain
Ó Catharnaigh - Kearney -
Co Meath & Offaly - chiefs of Teffia
Ó Ciardha - (O) Keary - Co
Kildare - the Southern Uí Neill, lords of Carbury
Ó Géibheannaigh - (O)
Keaveney - Co Galway - the Uí Maine
Ó Caoimh or Caim - O'Keefe
- Co Cork - descent from Art, King of Munster (742-762)
Ó Cianáin - (O) Keenan
- Co Monaghan/Louth (Oriel)
Ó Caomháin - (O) Keevan
or Kavanagh - Co Sligo - Uí Fiachrach
Ó Céileachair - Kelleher
- Co Clare - the Dal gCais
Ó Ceallaigh - (O) Kelly -
E Galway & S. Roscommon - Uí Maine (or Hy Many)
Ó Ceallaigh - (O) Kelly -
Co Meath - O'Kellys of Breagh
Ó Ceallaigh - (O) Kelly -
Co Laois - 7 Septs of Leix
Ó Ceallaigh - (O) Kelly -
Co Antrim and Down - Cinel Eachrach
Ó Caollaidhe - (O) Kelly or Kealy
- Co Kilkenny and Tipperary
Mac Cionath - MacKenna - Co Meath
and Monaghan - southern Uí Neill
Ó Cinnéide - Kennedy - Co Clare/Tipperary - the Dal gCais
- lords of Ormond
Ó Cionnaoith - (O) Kenny
- Co Galway/Roscommon - Uí Maine
Ó Caoinnigh - (O) Kenny or Keeney
- Co Leitrim/Donegal - lords of Muinter Kenny
Ó Coinne or O Coinnigh- Kenny
or MacKenna - Co Down
Mac Eochaidh - Keogh - S. Roscommon
- the Uí Mhaine, lords of Magh Finn
Mac Eochaidh - (Mac) Keogh - West
Tipperary
Mac Eochaidh - Keogh - N. Kildare
- same stock as the O'Byrnes
Mac Eoghain - MacKeon - Co Sligo/Leitrim
Ó Ciabháin - (O) Kevane
or Kavanagh - Co Cork - Corcu Laoidhe
Ó Cadhla - Kiely - Co Clare/Limerick
- the Dal gCais
Ó Céirín - (O)
Kieran or Kearns - Co Mayo - chiefs of Costello
Ó Ciarain - Kerin or Carey
- Co Cork/Clare
Ó Cinnfhaelidh - (O) Kinnealy
- Co Limerick
Chennselaig or Cinnsealach - Kinsella
- Co Wexford - see MacMurrough
Ó Ciardubháin - (O) Kirwan
- Co Galway - one of the Tribes of Galway
Ó Leathlaobhair - (O) Lalor or
Lawlor - Co Leix - 7 Septs of Leix
Ó Longáin - (O) Langan
or Long - Co Armagh chiefs
Ó Lonagáin - (O) Lanigan
- Co Tipperary chiefs
Ó Lorcáin - (O) Larkin
- Co Wexford - chief of Fothart
Ó Lorcáin - (O) Larkin
- Co Armagh - chief of Farney and West Uí Breasail
Ó Lorcáin - (O) Larkin
- Co Galway - the Uí Maine
Ó Lorcáin - (O) Larkin
- Co Tipperary - eranaghs of Lorrha
Mac Lochlainn - MacLaughlin - Co
Donegal (Inishowen) - the Northern Uí Neill
Ó fLaithbheartaigh - (O) Laverty
or Laherty - Co Donegal - lords of Aileach
Ó Limhain - (O) Lavin - Co
Roscommon
Ó Laochdha - Leahy - Co Cork
- Corca Laoighde
Ó Laoghaire - (O) Leary -
Co Cork
Ó Léanacháin - Lenaghan
or Lenihan - Co Roscommon, Limerick/Tipperary
Ó Leannain - Lennon - Galway,
Mayo and Fermanagh
Mac Giolla Mhín - MacLiveen
- South Down
Ó Longain - Long or (O)Langan
- Co Armagh
Ó Longaigh - Long - Co Cork
Ó Lochlainn - (O)Loughlin or
Lochlain - Co Clare - lord of Corcomroe
Ó Maoilsheachlainn - MacLoughlin
or O Melaghlin - Co Meath - of Malachy II (southern Uí Neill)
Mac Lochlainn - MacLoughlin - Co
Donegal - northern Uí Neill
Ó Labhradha - (O)Lowry or Lavery
- Co Down and Ulster
Ó Lúinigh - (O)Lunney
- Co Donegal/Tyrone - Cenel Moen
Ó Loideáin - Lydon, Leyden
or (O)Liddane - Co Galway/Mayo
Ó Loinsigh - (O) Lynch -
various including chiefs of the Dal Riada
Ó Loinsigh - Lynch - Co Galway
- Norman origin, one of the Tribes of Galway
Ó Laighin - Lyons or Lyne
- Co Galway and Kerry - Firbolg origin
Ó Liatháin - Lyons or
Lehane - Co Cork and Limerick - Uí Fidhgheinte (also a Norman name)
Mac Maolruanaidh - Macarooney -
Co Fermanagh
Ó Macdha - (O) Mackey - Co
Tipperary - an Ormond sept
Ó Madaidhin or Matudain- Madden
- East Galway - Uí Maine tribe
Mac or Mag Aodha - Magee - West
and East Ulster (respectively)
Mag Uidhir - Maguire - Co Fermanagh
- rulers of Fermanagh
Ó Meachair- Maher or Meagher
- North Tipperary
Mac Mathghamha - MacMahon - Co Monaghan
- rulers of Oriel (Airgialla)
Mac Mathghamha - MacMahon - Co Clare
- the Dal gCais, descent from Mahon O'Brien
Ó Mathghamhna - (O) Mahony
- Co Cork - Cenel Aodha, of the Eoghanacht
Ó Máille - O'Malley
- Co Mayo - chiefs of Fir Umaille, or Hymalia
Ó Maoil Eoin - Malone - offshoot
of the O'Connors of Connacht (?)
Ó Maoileoin - Malone - Co
Clare and Wexford - assoc. with the Abbey of Clonmacnois
Ó Mainnín - Mannion or
Manning - Co Galway - Pictish origin
Mac Maghnais - MacManus - Co Roscommon
- from Maghnais, son of Turlough O'Connor
Mac Maghnais - MacManus - Co Fermanagh
- from Maghnuis Maguire, son of Donn Mor
Ó Meadhra - O'Mara or O'Meara
- Co Tipperary - chief of Uí Fahy
Mac Giolla Mhartain - Martin or Gilmartin - Co Tyrone - Uí Neill
Ó Miadhachain - Meehan or Meighan
- offshoot of MacCarthys of Desmond
Ó Midhir - (O) Meere - Co
Clare - Anglo origin
Ó Mealláin - (O) Mellan
- Co Tyrone - Cenél Eóghain of Meallanacht
Ó Maoilédigh - (O) Melody
- Co Clare/Galway - Corcomroe
MacMeanman -MacMenamin - Co Donegal/Tyrone
- Cenél Conaill
Ó Muilleoir - Miller - Co
Antrim - Scottish origin, Clan McFarlane
Ó Mochain - Mohan or Moen
- Kilmacduagh, Galway and Killaraght, Sligo
Ó Maolmhuaidh - Molloy or Mulloy
- Co Offaly - Southern Uí Neill
Ó Maolmhuaidh - (O) Molloy
- Offaly - Southern Uí Neill, lords of Fercal
Ó Maoil Aodha - Molloy or Miley
- Co Roscommon / East Galway
Ó Maol Dhómhnaigh - Moloney,
Mullowney or Maloney - Co Clare - Chiefs of Kiltannon (Dal gCais)
Ó Manachain - Monaghan -
East Roscommon - rulers of the 3 Tuathas
Ó Manachain - Monaghan -
Co Fermanagh - the Fir Manach based in Lurg
Ó Maonaigh - Mooney - Co
Offaly and various other
Ó Móráin - Moran
- Co Mayo, near Ballina
Ó Mughráin - Moran
- Galway/Roscommon - the Uí Maine, chief of Criffon
Ó Mórdha - (O) More or
Moore - Co Laois - leading sept of the 7 Septs of Leix
Ó Murchain - Morgan - Co Managhan - mainly a name of Welsh
origin
Ó Muircheartaigh - Moriarity
- South Kerry - same stock as O'Donoghues
Ó Muirgheasa - Morris - Co
Sligo - the Uí Fiachrach
Ó Maolchathaigh - (O) Mulcahy
- Co Tipperyary
Ó Maoldúin - (O) Muldoon
- Co Fermanagh - chiefs of Lurg
Ó Maoldúin - (O) Muldoon
- Co Clare (Thomond) - the Uí Bloid
Ó Maoldúin - (O) Muldoon
- Co Sligo - Uí Fiachrach
Ó‘Maoldoraidh - O'Muldory
- Donegal - Tirconnel (MacAlinions)
Ó Maoldomhnaigh - Muldowney
- Co Kilkenny
Ó Maolchathail - (O) Mulhall
or Mulcahill - Co Laois - descendant of the devotee of (St.) Cathal
Ó Maolchalann - Mulholland
- N. Limerick - descendant of the devotee of (St.) Calann
Maoilchiaráin - Mulkerrin, Mulkieran
- Roscommon, Galway, Ulster - devotee of (St.) Ciaran
Ó Maolalaidhs - O'Mullally or
Lally - Co Roscommon - the Uí Maine
Ó Maolain - Mullan, Mullin(s),
Mullen, Mullane - Co Galway - descent from Maolan
Ó Maolain - Mullan, Mullin(s),
Mullen, Mullane - Co Derry - followers of the O'Cahans
Ó Maoilédigh - (O) Mulledy
- Co Westmeath/Offaly - Ballymaledy
Ó Maolain - Mullins and Mollins
- Cork and Monaghan (respectively)
Ó Maolagáin - (O) Mulligan
- Co Donegal - chiefs of Tir MacCarthain
Ó Maolchaoine - (O) Mulqueen
- Co Clare, Limerick - Dalcassian, from St. Caoine
Ó Maolruanaidh - Mulrooney
- Co Fermanagh and in Mayo/Roscommon
Ó Maoilriaghain or Mael Riain-
O'Mulryan or Ryan - Co Limerick/Tipperary
Ó Murnain - Murnane - Murnane
- Co Limerick
Mac Murchada - MacMurrough - Co
Wexford (Hy Chennselaig) - descendant of Murchadh
Ó Murchadha and Mac Murchadha -
Murphy - Co Tyrone - the Cenel Eoghain
Ó Murchadha - Murphy - Co
Wexford (Hy Felimy)- descendant of Murchadh or Murrough
Ó Muireachaidh - Murray -
Roscommon/Galway - the Uí Maine
Ó Muireadhaigh - Murray -
West Ireland - including a sept of the Uí Maine
Mac Muireachaidh - (Mac)Murry or MacMorrow
- Co Leitrim
Ó Muircheartaigh - Murtagh or
MacMurtry - Co Meath
Mac an Fhailghigh - Nally or MacNally
- Co Roscommon and Mayo - Norman origin
Mac Con Uladh - MacNally or MacAnally
- Co Armagh and Monaghan (S.E. Ulaid)
Mac Conmara - MacNamara - Co Clare
- the Dal gCais, rulers of Clancullen
Mac Conmidhe - MacNamee or Conway
- Co Derry and Tyrone
Ó Neachtain - (O) Naghten
- Co Clare - Dalcassian
Ó Neachtain - (O) Naughton or
Naghten - Co Roscommon/Galway - the Uí Maine
Ó Neill- O'Neill - Co Tyrone/Derry/Donegal
- the Cenel Eoghain, rulers of Tir Eoghain
Mac an Fhilidh - (Mac) Neilly, Neely
- Co Antrim
Mac Aonghasa - MacNiece - Co Antrim
Ó Niallain - Neilan or Neylan
- Co Clare (Thomond)
Mac an Airchinnigh - Nerney - Co
Roscommon - son of the erenagh
Ó Nuallain - Nolan - Co Carlow
- princes of Foharta (Fothairt)
Ó hIonmhaineáin - (O)
Noonan - Co Cork
Mac Phaidin - Patterson - Ulster
(and Scotland)
Ó Peatáin - Peyton or
Patton - Co Donegal - Cenél Moen
Ó Faolain- Phelan or Whelan
- Co Waterford - rulers of the Decies
Ó Coigligh - Quigley - Co
Mayo - the Uí Fiachrach
Ó Cuill - (O) Quill - Co
Cork and Kerry
Mac an Choilgh - MacQuilly or Cox
- Co Roscommon
Ó Caoindealbháin - (O)
Quinlan or Kindellan - Co Meath - southern Uí Neill
Ó Cuinn - (O) Quinn - Co
Tyrone - Cenel Eoghain
Ó Cuinn - (O) Quinn - Co
Clare (Thomond) - the Dal gCais
Ó Cuinn - (O) Quinn - Co
Antrim - the Glens of Antrim
Ó Cuinn - (O) Quinn - Co
Longford - same stock as O'Ferralls of Annaly
Ó Cuirc - (O) Quirke - Co
Tipperary - chiefs of Muscraighe Cuirc
Ó Raithbheartiagh - (O) Rafferty
- Co Donegal/Sligo
Mac Raghnaill - MacRannall or Reynolds
- Co Leitrim - lords of Muintir Eolais
Ó Reachtagáin - (O) Ratigan
- Co Roscommon - coarbs of St. Finnen
Ó Riordan - Rearden or (O)Riordan
- Co Tipperary/Cork - followers of the Lords of Muskerry
Ó Rodáin - (O) Reddan
- Co Clare - stewards to O'Brien and MacNamara
Ó Riagáin - (O) Regan
- Co Meath/Dublin - the Four Tribes of Tara
Ó Raogáin - (O) Regan
or Reagan - Co Limerick - the Dal gCais
Ó Riada - (O) Reidy - Munster
- king of Aradh in the 12th century
Ó Raghallaigh - (O) Reilly
- Co Cavan - Uí Briuin Breifne
Ó Maolcraoibhe - Rice - Co
Louth/Armagh - also of Welsh origin
Ó Ruanaidh or O Mael Ruanaid -
Rooney - Co Down
Ó Roghan - (O) Rogan - Co
Down - of Armagh and Iveagh
Mac Ruaidhri - MacRory or MacCrory
- Co Tyrone
Ó Ruairc - (O) Rourke - Co
Leitrim/Cavan - the Uí Briuin - rulers of Breifne
Ó Ruaidhín - (O) Ruane
or Rowen - Co Mayo - the Uí Fiachrach
Ó Ruadháin - (O) Ruane
or Rowen - Co Galway - the Uí Maine
Ó Riaghain - Ryan - Co Carlow
- chiefs of Uí Drona, also see Mulryan
Ó Scannláin - (O) Scanlan
- Munster
Mac Scannláin - (Mac) Scanlan
- Louth (Oriel)
Ó Scolaidhe - (O) Scully
- Co Westmeath
Ó Scolláin - Scullion
or (O) Scully - Co Derry
Ó Seasnáin - Sexton
- Thomond (also an English name)
Ó Seanachain- (O) Shanahan
- Co Clare - Uí Bloid (Dal gCais)
MAc Seanlaoich - (Mac) Shanly -
Co Leitrim - MacShanly of Dromod
Ó Seanáin - (O) Shannon
- Carlow/Wexford
Mac Giolla t-Seanáin - (O) Shannon
- Co Clare - son of the follower of St. Senan
Mac Searraigh - MacSharry or Foley
- Breifne, e.g. northern Leitrim, Sligo
Ó Seachnasaigh - (O) Shaughnessy
- Kiltartan, Co Galway - the Uí Fiachra Aidhne
Ó Seaghdha or Segda - (O) Shea
- South and East Kerry - Lords of Iveragh
Ó Siodhacháin - Sheehan
- Co Limerick/Cork - the Dal gCais
Ó Sirideáin - Sheridan
- Co Longford/Cavan
Ó Seiridh or Mac Seiridh - O'Sherry
or McSherry - Oriel, e.g. Monaghan and Armagh
Mac an Ghirr - Short, Shortman or Shortel
- Unknown
Ó Sluaghain or O’Sluagahadain -
Sloan - of Scottish origin
Mac Gabhann - Smith
or MacGowan - Co Cavan
Ó Sóchlacháin - (O)
Solan, Solahan - Co Mayo
Ó Suileabhain - (O) Sullivan
- Co Kerry - the Eoghanacht - O'Sullivan Mor of Kenmare Bay
Ó Suileabhain - (O) Sullivan
- Co Cork - Eoghanacht - O'Sullivan Beare of Beara Peninsula
Mac Suibhne - Sweeney or MacSweeny
- Co Donegal - descent of Scottish chief in Argyle
Ó Tarpaigh - (O) Tarpy, Tarpey,
Torpey - Co Sligo - lords of Carra
Mac Tighearnáin - (Mac) Tiernan
or Kiernan - Co Cavan - chiefs of Teallach Donnchadha
Mac Tighearnáin - (Mac) Tiernan
- Co Roscommon - descent of O'Connor
Ó Tighearnaigh - (O) Tierney
- Co Mayo - lords of Carra
Ó Tighearnaigh - (O) Tierney
- Co Galway, Limerick and Tipperary - Ormond's Fir O'Tyernie
Ó Tuathail - O'Toole - Co
Kildare and Wicklow - descent from Tuathal, king of Laigin
Ó Treasaigh - (O) Tracy or Treacy
- Co Cork, Galway, Leix (Lords of Slievemargy)
Ó or Mac Tréinfhir - Traynor
- Co Meath
Ó Tiobraide - (O) Tubridy
- Co Clare
Ó Tuama - O'Twomey or Toomey
- Co Cork, and Co Limerick
Mac an Bháird - (Mac) Ward
- Co Donegal and Galway
Ó Faolain - Whelan or Phelan
- Co Waterford - rulers of the Decies
|
|
Index of births for the year 1890 - from the indexes
of the General Registrar's Office
|
|
RED THREAD GENEALOGY |