The Mac Cárthaigh Riabhach seated themselves as kings of Carbery in what is now southwestern County Cork including Rosscarbery in the 13th century.[1][2] Their primary allies in the initially small territory itself were O'Donovans,[1] and members of the Ui Chairpre; both were recent arrivals, gaining their lands from the O'Mahonys of Eóganacht Raithlind and the O'Driscolls of Corcu Loígde. The historical record for this period is very confused and a precise sequence of events cannot be reconstructed. A portion of Carbery was conquered around 1232 by Donal Gott MacCarthy, King of Desmond, from whom the dynasty descend.[3] His son Donal Maol Mac Carthaigh, was the first ruler of the new principality. Their descendants would expand their territories considerably and forge a small, wealthy kingdom distinct and independent from the larger Kingdom of Desmond, as well as largely independent from the Earldom of Desmond and from England, which would last into the early-mid 17th century.[4]
Fínghin Mac Carthaigh, the victor for Gaelic Desmond in the Battle of Callann and other campaigns, is considered to belong to the Mhic Carthaigh Riabhach, being a son of Donal Gott.[5] They were in frequent conflict with the line of the MacCarthy Mor, and the MacCarthys of Duhallow and Coshmaine, all of which were generally in conflict with the Fitzgeralds and FitzMaurices which comprised the lines of the Earl of Desmond and the Earl of Kildare, respectively.[6]
As patrilineal descendants of the 4th Prince, but not the 5th Prince, the MacCarthys of Dunmanway, belonging to the MacCarthy Glas[16][17][18] and MacCarthy Duna[19][20] septs, are not technically MacCarthys Reagh. However, most historians and genealogists refer to all descendants of Donal Gott as MacCarthys Reagh, and it is the case that, should the "senior line", descendants of the 5th Prince, fail, then the MacCarthys of Dunmanway would become the "new" Princes of Carbery.
^National Library of Ireland Genealogical Office Ms. 111f, fol. 125 'Copy of confirmation of arms to the descendants of John Leader MacCarthy and to his son, Francis Leader MacCarthy of Chessington, Salop., with mention of recorded descent from Donal Reagh MacCarthy "The MacCarthy Reagh" of Kilbrittain Castle, who died 1414; 17 Sept. 1937'
^National Library of Ireland Genealogical Office Ms. 176, pp. 459–63 'Pedigree of MacCarthy, Kings of Desmond, MacCarthy Reagh, the Bernard MacCarthys and Leader MacCarthys 1045-1937'
O'Keeffe, Eugene (ed. and tr.), Eoganacht Genealogies from the Book of Munster. Cork. 1703. available here
Ó Murchadha, Diarmuid, "The Battle of Callan, A.D. 1261", in Journal of the Cork Historical and Archaeological Society, Vol. LXVI, No. 204. July–December 1961. pp. 105–116.
Ó Murchadha, Diarmuid, Family Names of County Cork. Cork: The Collins Press. 2nd edition, 1996.
