Mac Cahern or Mac Caughran - Irish / Mheic Eachrain. Also used as synonyms for Mac Gahern, which see.

O Caherny - Irish / Ua Catharnaigh - catharnach / warlike. A Sept / Family branch, who had their territory in Co. Offaly in the north - west of Southern Leinster. See also - Fox and Kearney.

Mac Caherty or Mac Caugherty. A Sept / Family branch, who had their territory in Co. Down in the south - east of the Ulster Province where they were used as forms of Mac Cafferty, which see.

O Cahill - Irish / Ua Cathail - cathal / cat - ualos / strong in battle. A Heberian Dal gCais Sept / Family branch, who had their territory in Co. Galway in Southern  Connacht where they were the Chiefs of Kinelea at Kilmacduagh on the Co. Clare border in Thomond / Tuaisceart Mhumhain / Northern Munster. There they were Dalcassian Chiefs with the O Flatterys and were removed from their original territory by the Ui Fiachrach Aidne O Shaughnessys. Now in Co. Clare and Co. Cork in the Munster Province. Ancestor: *91.Cas (Dal gCais) the King of Thomond.

O Cahill - Irish / Ua Cathail. A Sept / Family branch, (Descended from Davnit / Damnat / fawn) who was the wife of 95.Aed "Bennan" the Heberian Eoghanacht Locha Lein 9a King of Munster who died in 619 / 21 AD. She is also the ancestress of the O Carrolls, O Flynns and O Moriartys in Co. Kerry in the south - west of the Munster Province. The O Cahills were Chiefs in Co. Tipperary in the north - west of Ormond / Aur Mhumhain / North Eastern Munster, and in Co. Carlow in Southern Leinster. Ancestors: *85.Eoghan "Mor" (Eoghanachta), *84.Ailill "Oluimm" the 1st King of Munster.

O Cahill. A Heremonian Ui Cobhthaigh Ui Felim Dal Cuinn Colla da Crioch Sept / Family branch. Ancestors: *85.Murray / Muiredach "Colla da Crioch" / "Focrith"- of the Two Countries, *84.Eochy / Echu "Doimhlen," *83.Cairbre "Liffeachair" the 116th King of Tara / Ireland.

Mac Cahill - Irish / Mheic Cathail - cathail / valour. A Sept / Family branch, who had their territory in Co. Donegal in the north - west of the Ulster Province and Co. Cavan in Southern Ulster. See also - Mac Call.

O Cahir - Irish / Ua Cathaoir (Descended from Cahir) A Sept / Family branch, who had their territory in Co. Clare in the north - west of Thomond / Tuaiscert Mhumhain / Northern Munster.

Mac Cahir. A Heremonian Ui Laoghaire Ui Lughaidh Cu Corb Ui Cheinnselaig Mac Murrough Sept / Family branch, of the Kavanaghs, which see, in the 16th Century AD that was also used by other Leinster Province Families.

Mac Cahon. Used as a variant usually for Mac Caughan, which see, and sometimes for Mac Gaghan, which see, in the Ulster Province. Not connected to the Mac Cahans / Mac Keanes in Co. Clare in the north - west of the Munster Province.

Mac Caig. An anglicized form of Mheic Thaidhg. A Sept / Family branch, who had their territory in Co. Galway in Southern Connacht. See also - Mac Teige.

Cain or Cane. English names used in Co. Mayo in the mid - west of the Connacht Province by the Kanes to anglicize their names.

Cairns. Scottish toponymic origins. They were in the Ulster Province. It was also occasionally used for Kieran, which see.

Calderwood. See - Catherwood.

Caldwell. An English name used by the Heremonian Ui Cobhthaigh Ui Felim Dal Cuinn Colla da Crioch Sept of O Horish - Irish / Ua Huarghuis, which especially see - and O Horiskey - Irish / Ua Huairisce who had their territory in Co. Tyrone in Central Ulster. Also used by the Mac Cullivans and Mac Colavins, which see, Irish / Mheic Conluain who had their territory in Co. Cavan in Southern Ulster.

Cale -

Mac Call. Used by the  Campbells - Irish / Mheic Cathmhaoil, which see, to also anglicize their name. A Heremonian Ui Cobhthaigh Ui Felim Dal Cuinn "Northern" Ui Niaill Cenel nEogain Cenel Fheardaigh Theas Sept / Family branch, who had their territory in Co. Armagh and Co. Tyrone in the Ulster Province. Also used as a synonym for Mac Cahill, which see. See also - Caulfield. Ancestors: *88.Eogan the 1st King of Aileach (Cenel nEogain), *87.Niall of the Nine Hostages the 126th King of Tara / Ireland (Ui Niaill).

Mac Calla. Used as a variant for Mac Caully, which see, in Co. Donegal in the north - west of the Ulster Province. Also used in Co. Armagh in the south - east of Ulster for Mac Call, which see.

O Callaghan. A Heremonian Ui Cobhthaigh UI Felim Dal Cuinn Colla da Crioch Sept / Family branch. Ancestors: *85.Murray / Muiredach "Colla da Crioch"/ "Focrith"- of the Two Countries, *84.Eochy / Echu "Doimhlen," *83.Cairbre "Liffeachair" the 116th King of Tara / Ireland.

O Callaghan - Irish / Ua Ceallachain - cellach / strife. A Heberian Eoghanacht Chaisil Sept / Family branch, who were Kings and Chiefs in Co. Cork in Desmond / Des Mhumhain / Southern Munster, and Chiefs in Co. Mayo in the mid - west of the Connacht Province and Kings and English appointed Viscounts in Co. Tipperary in the north - east of Ormond / North Eastern Munster. Descended directly from *104.Callaghan / Ceallachan "Chaisil" the great Eoghanacht 34th King of Cashel / Munster who died in 952 / 4 AD after taking on the Vikings head on and nearly succeeding. In the 11th Century AD his grandson, *106.Murrough / Murchad (sea battler) Ua Ceallachain began to use his Christian Gaelic name as his surname. His great - grandson, 105.Carthy / Carrthach (The Loving One,) became the ancestor of the Mac Carthys who began a Family succession struggle with the O Callaghans well into the 12th Century AD, with the Mac Carthys eventually becoming more dominant. At the end of the 13th Century AD the O Callaghans had "O Callaghans Country" / Pobal Ui Chellachain, which was a part of Co. Cork in Desmond / Southern Munster on both sides of the River Blackwater west of Mallow with castles at Clonmeen and Dromaneen were they continued to rule for 400 years. 1537 - 1578 AD Donough / Donnchad O Callaghan was their Chief who perfected the art of cattle raids / creach throughout Munster carrying out 200 altogether. In the 17th Century AD after the Oliver Cromwell Invasion their territory was also Confiscated by the English and they were transported to "Hell or Connacht" into Tulla in Co. Clare in the north - west of Thomond / Northern Munster where there is O Callaghan's Mills. "The O Callaghan" today is Juan O Callaghan. Ancestors: *104.Callaghan / Cellachan "Caisil" the 34th King of Cashel / Munster, *103.Buadchan, *102.Lachtnae, *101.Artgal, *100.Snedgus, *99.Donngal / Dungalach, *98.Faelgus, *97.Nad "Fraich," *96.Colgan / Colgu the 15th King of Cashel / Munster, *95.Failbe "Fland" the 11th King of Cashel / Munster, *94.Aed "Dubh," *93.Criffan / Crimthann, *92.Felim / Feidlimid the 4a King of Cashel / Munster, *91.Angus / Oengus the 3rd King of Cashel / Munster, *90.Nad "Froich" the 2nd King of Cashel / Munster, *89.Conall "Corc" the 1st King of Cashel / Munster, *85.Eoghan "Mor,"(Eoghanachta) *84.Ailill "Oluimm" the 1st King of Munster. See also - O Kealaghan.

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