As early as the 6th century, the Corcu Duibne, a kin group which was to later branch into the O'Shea, O'Falvey, and O'Connell families, had become well established on the Dingle and Iveragh peninsulas in the west of what is now County Kerry. Archaeological evidence, in the form of Ogham stone inscriptions, allows us to ascertain the approximate location and extent of their lands. However, before we examine the archaeological evidence, a quick survey of the ancient genealogies is in order.
According to O'Hart, (1) the O'Shea family descends form Corc, a son of Cairbre Musc, who was a son of Conaire II, the 111th High King of Ireland. They are thus part of the broader kinship group known as the Clanna Degaidh. Although none of the sources consulted gives a date of birth or death for either this Corc or for Cairbre Musc, O'Hart gives the death of Conaire II as A.D. 165.(2) This date is found to be the same as that given in the Annals of the Four Masters. (3)
Cairbre Musc was, in turn, a powerful chieftain, but legend has it that the fathering of Corc was somewhat less than respectable. According to Keating:
It happened about this time [that] Carbri Musg had acquired great power in Munster, and that during his time misfortunes and failures of crops came upon that principality. Nor, indeed, was that to be wondered at, for it was through incest that Corc had been borne to him by Dubinn, who was his own sister; for they were both children of Conari, son of Mogh Lamha, and of Saradh, daughter of Conn of the Hundred Battles. When, then, the nobles of Munster had taken notice that misfortunes had fallen upon their country during the rule of Carbri, they demanded of that chieftain, what it was that had taken its produce and good luck from their land. And [Carbri] answered them, and said that it was incest that he had himself committed with his own sister, namely, with Dubinn, and that she had borne him two sons, namely, Corc and Cormac. When the Chiefs of Munster heard this, they demanded to get the sons, in order that they might destroy them, by consuming them with fire, and then cast their ashes into the running stream. "Let that be done by you" said Dinach the Druid, "as far as Cormac is concerned; but let not Corc be killed by your hands. Let him be given to me, and I shall take him with me out of Eri." His request was granted him, and he took the child with him to Inis-Baei [now Bear Island, in Bantry Bay], where he found a vestal named Baei, under whose protection he placed him. (4)
While the account is legendary, it should be mentioned that three important kin groups are connected to this genealogy. As mentioned above, Cairbre Musc was supposedly the progenitor of the Muscraige (an extended kin group in West Kerry, of which the Corcu Duibne is a sub-group). This Cairbre Musc had two brothers, Cairbre Riada and Cairbre Baiscind, from whom are said to descend the Dal Riada (a dynasty which evenutally took control of the Scottish territory across the channel from Ulster), and the Corcu Baiscind kin group (situated in what is now County Clare), respectively.
Although it is tempting to dismiss allusions to the ancient genealogies as nothing more than fanciful inventions which hoped to link various kin groups to royal lineages, we find compelling parallels in the surviving archeological record.
Very few examples of writing from the 6th and 7th centuries survive in their original form. Most of the histories, genealogies, and religious writings of the period exist now in copies from the late Medieval period, or were included in larger compilations which also date from later centuries. One notable exception to this is the Ogham inscriptions found on numerous stones in western Ireland.
Ogham is a written language made up of a system of slashes and lines, generally cut into the edge of a stone which was erected for that purpose. Since most Ogham stones date from the 5th to 7th centuries,v a study of their inscriptions (generally memorials) can suggest an approximate area in which a kin group was dominant.
There are at least four surviving Ogham stones on the Dingle Peninsula which bear the name "DOVINIAS," a Latin version of Dubinn, or "Duibne." This, asserts Harold Mytum, was an ancestress associated with the Corcu Duibne, and thus, "the distribution of ogham stones carrying this inscription may therefore indicate the extent of the tribe and its túath [domain] in the fifth century." (6) The parallel to Keating's account is quite clear.
Another ogham find on the Iveragh Peninsula (the area most specifically associated with the O'Sheas) has a truncated version of this same name, "DOVIN." A Tribal Name Map illustrates a number of tribal ancestral names found on oghams and their locations.
It may also be significant to note that the ancestor "CONURI" is indicated in the lands north of the Dingle Peninsula (where "DOVINIAS" is indicated). This probably signifies the lands of the Corcu Baiscind, who were also descended from Conaire II ("Conuri").
Placing these tribal names in a wider context with the powerful Eóghanacht dynasties, we can make an educated guess at the extent of Corcu Duibne lands in the 6th century. Of course, Ireland was rather sparsely populated at that time, and it is likely that considerable areas of land existed between the lands of one kin group and another. The areas of probable Corcu Duibne influence are shown on Map #1.
As populations grew in the 9th and 10th centuries, it became necessary to identify kinship groups according to more specific, that is, more recent, ancestry. Groups, such as the Corcu Duibne, which had flourished in the 7th and 8th centuries, became too numerous and widespread to effectively control a single túath within the extended family group. The derbhfine (male children of a common great-grandfather) of the ruling family was eventually dwarfed by the larger group of descendants from the remote ancestor (in the case of the Corcu Duibne, a 3rd-century ancestor).
The problem was solved by the designation of a more recent ancestor as the patronymic ancestor of the kinship sub-group, or Sept (a term that is more accurate than the broader term 'clan'). In this way, the Uí Séaghdha, Uí Failbhe, and the Uí Conaill septs branched out from the Corcu Duibne in the 10th century (Map #2).
The Uí Séaghdha seem to have been most closely associated with the northern part of the Iveragh Peninsula, in the area known as Uí Rathach (roughly corresponding to the modern Barony of Iveragh). It is interesting to note that the form of "Uí Rathach" looks very much like the archaic construction of sept names (e.g., Uí Séaghdha - descendants of Séaghdha). It is possible that "Rathach" refers to another ancestor of the O'Sheas which preceded Séaghdha, although the latter eventually became the "ancestor of choice" when the sept name was finally fixed. At present, though, this is only conjecture.
At times, up to and including the 12th century, the Uí Séaghdha controlled not only the Iveragh territories, but occasionally were in control of the entire lands of the Corcu Duibne (being mentioned in the annals as rí Corca Dhuibhne or "kings of Corcu Duibne"). They appear to have held the Corcu Duibne title in alternation with the Uí Failbhe (O'Falvey) sept, who, as we have established, were their kin.
To the East, the septs of the Eóghanacht gradually gained control over much of Munster. Although challenged in the 11th and 12th centuries by the Dal gCais (progenitors of the O'Briens), the Eóghanacht, and in particular the Eóghanacht Chaisil (progenitors of the MacCarthy Mór dynasty) grew in power, securing the Kingship of Munster. One of the greatest rulers of this dynasty, Cormac III MacCarthy Mór, came to the throne in 1123. To solidify his rule over Desmond (southern Munster), he expelled a number of the Lords in that region (including the King of Eóghanacht Locha Léin, a related sept to his own):
[A.D. 1124] Ua Muirchertaig, King of Eóghanacht Locha Léin, Cú Luachra Ua Conchobuir, King of Ciarraige, and Murchad Ua Séaghdha, King of Corcu Duibne, were banished by Cormac, son of MacCarthaigh. (7)
While this banishment theoretically ended O'Shea control of Corcu Duibne, the O'Sheas did remain a force in the region. The Annals of the Four Masters suggest that the O'Sheas may have continued to fight for their former territories, since, in 1158, "Ua Failbhe, King of Corcu Duibne, was slain by the Uí Séaghdha." (8) A conjectural genealogy of the Corcu Duibne kings can be constructed from the surviving literary sources and annals.
At about this time, a branch of the Uí Séaghdha moved east, presumably to seek a more favorable situation. While the majority of members of the sept appear to have stayed in Kerry (as evidenced by the concentration of the name in Kerry to this day), those that moved east into the counties of Kilkenny and Tipperary became powerful landowners, retaining their prominence into the 17th century.
Meanwhile, the ancestral lands in western Kerry changed hands a number of times. The Uí Failbhe appear to have lost control of the lands on the Iveragh peninsula by the early 13th century, for in 1214, the Galls (Vikings) "overran the whole of Munster" and in 1216, Corcaguiney was divided between two Anglo-Norman Lords, John de Clahull and Robert de Marisco (son of the Justiciar of Ireland, Geoffrey de Marisco, with much of the surrounding lands (probably including Iveragh) being granted to the Geraldine Family (FitzGeralds). (9) Later, "in 1310 Mac Carthaigh's freemen and aos grádha [lesser feudal nobles] all held their lands in the district of Uibh Ráthach [i.e., Iveragh]." (10)
An exact account of the control of Iveragh from 1124 until the collapse of the Kingdom of Desmond in 1596 with the death of the last reigning MacCarthy King (Donal IX), remains the subject of further research, but it is clear that the Lordship of Iveragh remained mostly under the control of the MacCarthy Mór kings, or Lords which held the lands on the basis of a feudal arrangement with them. These lands may have been granted to feudal lords more than once during the period, but eventually were granted to the O'Mahoneys, who are listed as the Lords of Iveragh as late as 1588 (11) (Map #3).
The current MacCarthy Mór states that "it is an historical fact that the O'Mahonys settled in Kerry in the fourteenth century, and received large grants of land from the kings of Desmond."(12) Other accounts mention a date of 1355, though this may be unreliable. (13) In any case, we may place the O'Mahoney control of Iveragh roughly in the period of 1350 to 1600, which leaves a considerable span of time (c. 1220 - 1350) undocumented.
In the period from 1124 to 1600, Corcu Duibne (or Corcaguiney) seems to have slipped from the control of the Uí Failbhe (O'Falveys), since they are not mentioned in Sir George Carewe's survey of the Irish military forces in Desmond in the 1580s (14), indicating that they had ceased to be a military force of any consequence by that time. It is possible that they were also expelled in the 12th century by the MacCarthys.
In conclusion, we may develop at least a broad outline of the earliest origins of the Uí Séaghdha by studying the admittedly fragmentary references in the surviving annals and archeological record, and searching for parallels in the "semi-legendary" ancient genealogies and histories. It is often said that legends have some basis in fact. The story of Cairbre Musc's son, Corc Duibne, contains many mythical facets, but the fact remains that as early as the 5th century, a clearly defined kin group, the Corcu Duibne, dominated much of the Iveragh and Dingle peninsulas in western Kerry.
The group's existence alone does not validate the account which claims that these people are descended from the 3rd-century figure Corc Duibne, but it does show that during the earliest history of the tribe, members claimed descent from a common ancestress, "Dovinias" (or Duibne). The connection may be impossible to document, but the parallels between the archaeological record and the ancient genealogies are compelling. We may be certain, however, that the O'Sheas descend from a kinship group which controlled considerable territories on the Dingle and Iveragh peninsulas for upwards of 800 years.
(1) O'Hart, John. Irish Pedigrees: The Origin and Stem of the Irish Nation. (Dublin: J. Duffy, 1892): I, 757.
(2) Ibid, 59.
(3) Annala Rioghachta Eireann. John O'Donovan, ed. I, 107.
(4) Keating, Geoffrey. The History of Ireland. Edited by John O'Mahoney, reprinted Kansas City: Irish Genealogical Foundation, 1993: I, 337-8.
(5) Richter, Michael. Medieval Ireland. (New York: St. Martin's Press, 1988): 31.
(6) Mytum, Harold. The Origins of Early Christian Ireland. (London: Routledge, 1992): 141.
(7) MacAirt, S., ed. Annals of Inisfallen. (Dublin, 1951): 285.
(8) Annala, s.v. 1158.
(9) Otway-Ruthven, A.J. A History of Medieval Ireland. (London: Ernest Benn , 1968): 86-7.
(10) Annals of Inisfallen, s.v 1310, quoted in Simms, Katherine. From Kings to Warlords. (Woodbridge, Suffolk: The Boydell Press, 1987): 86.
(11) Carewe, Sir George (of the Irish Privy Council), c. 1580, reproduced in MacCarthy Glas, The Life and Letters of Florence MacCarthy Reagh. (London, 1867): 9.
(12) The MacCarthy Mór. Historical Essays on the Kingdom of Munster. (Kansas City, MO: The Irish Genealogical Foundation, 1994): 156.
(13) Ibid.
(14) Carewe, ibid.