Dalcassians

In their own genealogies, the Dál gCais traced their line back to their eponymous ancestor and progenitor Cormac Cas, who is said to have lived in the 2nd to 3rd century. They make him a second son of Ailill Aulom from the Deirgtine, a King of Munster and Leath Moga more generally, associated in a story with the goddess Áine of the Tuatha Dé Danann during the Cycles of the Kings of Irish mythology. Cormac Cas himself was purported to be the younger brother of Eógan, founder of the Eóganachta, who would go on to rule Munster for many centuries. While this was taken on face value for a long time, later Irish scholars came to question its validity, regarding it as a politically motivated fabrication. The Dál gCais were becoming powerful in the 10th century, with Mahon and his brother Brian Bóruma taking the throne in Munster from the Eóganachta; claiming ancient kinship with their rivals would have boosted their legitimacy.

Aerial view of the River Shannon, the area where the Dál gCais grew in power.

It is claimed by current scholarship that the Dál gCais were instead a branch of the Déisi Muman.[6][7] The Déisi Muman held a vassal kingship in Munster under the Eóganachta, significant in scope, consisting of what is today Waterford and its environs. As time went on branches also emerged around the River Shannon, as part of the Déisi Muman moved north-westerly between the 5th and early 8th century; they were called the Déisi Deiscirt and the Déisi Tuisceart. It is from later, more northerly branch, which the Dál gCais are said to ultimately find their true ancestors.[6] The first recorded mention of their adoption of the new name Dál gCais specifically is in the Annals of Inisfallen for the year 934, which records the death of their king Rebachán mac Mothlai.

The Déisi Muman themselves are subject of The Expulsion of the Déisi epic in the Cycles of the Kings, which is set during the time that Cormac Ulfada was High King of Ireland. The story describes the expulsion of the Dal Fiachrach Suighe; kinsmen of the Connachta and descendants of Fedlimid Rechtmar; from Tara, coming to settle in Munster after many battles. Upon becoming the Déisi Muman, one branch then sailed across to Britain in the 4th century, coming to rule Dyfed. Their presence in Britain may have been initially supported by Magnus Maximus, Roman Emperor, as part of a policy of backing Gaelic vassals to be seafaring defenders of the shores of Britain facing the Irish Sea from pirates.[8] Eoin MacNeill has pointed out that they were not the only Irish colony in the area, with the Uí Liatháin also powerful.

The adoption of the name Dál gCais and the ascent of the group to greater power, began to take place during the 10th century with internal political transition.[7] With the death of Rebachán mac Mothlai, the leadership of the Déisi Tuisceart shifted from the Uí Aengusa kindred to their junior relatives the Uí Thairdelbaig.[7] It was during the time of Kennedy,[7] who styled himself King of Thomond, that the Dál gCais began to challenge the Eóganachta; though Kennedy was defeated at the Battle of Gort Rotacháin by Cellach Caisil, King of Munster in 944. The actual reason for this sudden surge has been much debated and one frequently discussed thesis is that it was a political scheme of the Uí Néill, intending to use the Dál gCais as proxies to further weaken the power of the Eóganachta.[9]

Brian Bóruma, High King of Ireland, perhaps the best known historical figure of the Dál gCais.

Kennedy's children built on their father's achievements. His daughter Órlaith became Queen consort of Ireland, after she married Donagh Donn, a High King of Ireland from the southern branch of the Uí Néill. Mahon became the first Dál gCais to gain the kingship of Munster, after he seized the Rock of Cashel from Molloy of the Eóganachta. Leading up to this he had defeated the Norse under Ivar of Limerick at the Battle of Sulcoit in 968. After Mahon was captured by Donovan in 976 and murdered by Molloy, the Eóganachta returned to the throne at Cashel for two years, but Mahon's younger brother Brian Bóruma, a seasoned military man from the early campaigns, would desire vengeance.

A campaign in 977-78 led to the defeat and death of Ivar, with an engagement at Scattery Island being the most significant. Brian retained the formerly Norse Limerick for its trading power and naval strength. The Dál gCais took back Munster at Belach Lechta the same year, killing Molloy in the process. Ambition saw Brian look next to the territories of Malachy II, High King of Ireland. A closely contested war of 15 years ensued, with the naval ability of the Dál gCais paying off as a truce was called by Malachy in 997, recognising Brian's overlordship of Leath Moga. They became allies against the Norse Dublin and the Laigin who under Máel Mórda, King of Leinster had risen against Brian's claims. The latter were subdued at Glenmama in 999, before rebelling again in 1014 at Clontarf where Norse power in Ireland was finally broken, though Brian died in the process. In the interim, Malachy had passed the High Kingship to Brian in 1002 and he built strong Christian links to Armagh.

After the death of Brian, his two established surviving sons; Donagh and Teague; struggled in an internal Dál gCais rivalry for dominion. While Donagh was High King, many other Irish kings allied against him, including Leinster, Connacht, and Ulster. Deposed in 1063, he fled to Rome, with some sources claiming he granted Pope Urban II the Irish crown, this is controversial, however.[note 1] Teague's son Turlough took up the reins in a lasting alliance with the powerful Dermot Kinsella, King of Leinster. Not a military leader, Turlough was instead a capable politician, the Cogad Gáedel re Gallaib glorifying Brian's feats would be authored during his lifetime. Turlough's son Murtagh would be the last High King from the Dál gCais of the medieval period, reigning between 1101–19. Murtagh attempted to make the Irish kingship more along the lines of European monarchies and was involved in foreign affairs (allying with Arnulf de Montgomery in the Welsh Marches against Henry I, King of England), trying to extend Irish influence beyond internal rivalries.

The septs of the Dál gCais developed over time, with new ones breaking off to form separate surnames at different times, but all claiming to share the same paternal line (with a few biological exceptions along the way due to adoption or extra-marital issue). Their eponymous founder Cas had several sons; two of them gave their names to the Uí Bloid and Uí Caisin kindreds, another founded the Ui Fearmaic. As the proto-Dál gCais moved up into what is today East Clare, these became associated with rooted tribal areas, but were themselves internally divided into any other septs.[10]

Tree graph showing relationships between the Dalcassian septs.[note 2]

The senior line descended from Cas' first son Bloid and they provided the Kings of Thomond. Initially the leaders of the tribe were a sept known as the Uí Aengusa from which descends O'Curry, O'Cormacan and O'Seasnain. However, during the 10th century, this passed to the junior Uí Thairdelbaig. It is this kindred which would furnish the High Kings of Ireland and the Kings of Thomond including Brian Bóruma. From the Uí Thairdelbaig came O'Brien, O'Kennedy (who were Kings of Ormond), MacConsidine, MacMahon, O'Reagan, MacLysaght, O'Kelleher, Boland, Cramer, Kearney, O'Casey, Power, Twomey, Eustace, Ahearne, MacGrath, Quick, O'Meara, Scanlan, MacArthur, Cosgrave, O'Hogan, Lonergan and others.[11][12] O'Noonan and Coombe are other notable Uí Bloid descendants.[11] A younger brother of Carthann Fionn (who both the Uí Thairdelbaig and Uí Aengusa derive) named Brennan Ban stands at the head of the genealogies for the O'Brennan, Glinn, Muldowney and O'Hurley septs.[11]

Although a junior line, the Uí Caisin continued to have a prominent role and the leader of their kindred in Thomond were the MacNamara, who as Lords of Clancullen, were the second most powerful family after the O'Brien.[13] Other families descended from the branch of Carthann (son of Caisin) include Harley, Flood, Torrens, Stoney, Hickey, O'Hay, Clancy, Neylon and Flattery.[14] Carthann had brothers named Eocha and Sineall from whom descends the O'Grady, Tubridy, Hartigan, Durkin, Killeen and Hogg.[15][16][17] In addition to this, there are the Ui Fearmaic[18] who claim to descend from Aengus Cinathrach, a brother of Caisin and Bloid. This kindred included the O'Dea as leaders, as well as the O'Quin, O'Griffin / O'Griffey (chieftains of Cineal Cuallachta), O'Heffernan, Kielty and Perkin.[19] [20][21]

Within the traditional Gaelic culture of Ireland, society rested on the pillars of the tribal nobility, bardic poet historians and priests.[22] Different families had different roles to play and in many cases, this was a hereditary role. However, the nature of this system, known as tanistry was aristocratic ("rule by the best") in the truest sense, in that if the tribe thought a younger male member of the family was more suitable to succeed to a role than an older sibling, then they could. The Norman and wider European concept of strict primogeniture was not completely adopted until after some of the families joined the peerage of Ireland.

The most powerful Dalcassian family of the hereditary Gaelic nobility were the O'Brien (Kings of Thomond), followed by MacNamara (Lords of Clann Cuilean), O'Kennedy (Kings of Ormond), MacMahon (Lords of Corca Baiscinn),[2] O'Grady (Lords of Cinél Dongaile) and O'Dea (Lords of Ui Fearmaic). Some of these families later joined the peerage of Ireland after the surrender and regrant to the Tudors during the 16th century. The O'Brien was initially Earls of Thomond, but later became Barons Inchiquin which they hold to this day. The O'Grady was Viscounts Guillamore, while the O'Quins became Earls of Dunraven.[19] A branch of the MacMahon family became Marquis de MacMahon d'Eguilly[3] in the Kingdom of France, later raised to Dukes of Magenta under Emperor Napoleon III.

The Clancy sept was the hereditary Brehons of Thomond and held a very powerful position when it came to the law in the kingdom.[23] Even after the end of the Gaelic order, they continued to play a role, providing a High Sheriff of Clare in the form of Boetius Clancy.[23] Famously participating in the Contention of the Bards in support of the honour of the tribe, the MacBrody sept were the principal poets and historians of the Dál gCais over the course of centuries.[24][25] The O'Hickey and Neylon[26] sept would serve as hereditary physicians to the Dalcassians of Thomond. After the Norman Butler dynasty took Ormond, the Dalcassian sept of O'Meara became their hereditary physicians, this line included Barry Edward O'Meara, who was with Emperor Napoleon I in exile at St. Helena.

The Kings (or Chiefs) of the Dal gCais where nominally vassals (oir-righthe) of the Eoganacht King of Munster until the reign of Cinnéidigh Mac Lorcáin but would have exercised internal autonomy as regional rulers. Cinnéidigh was the first Dalcassian King to lead an army beyond his own territory and was acknowledged as King of Thomond by his death. His son Mathgamain built on these achievements, capturing Cashel and becoming King of Munster. The best-known member of this dynasty, Brian Boru, took over after his brother Mathgamain's death, reclaimed the Munster kingship and eventually succeeded in establishing himself as High King of Ireland before his famous death in the Battle of Clontarf. The Dal gCais under Brian's dynasty, the Ua Briain would provide a further three High Kings of Ireland but by the 12th century had retreated back to Thomond where they held the provincial kingship for a further 400 years. During this time they defeated challenges by the Norman de Clare family who used strategies of divide and rule by supporting Clann Brian against Clann Tadhg in their succession struggle.[27] Richard de Clare was decisively defeated in the Battle of Dysert O'Dea in 1318 and Norman power in Thomond was ended. In 1543 Murchadh Carrach Ó Briain, under pressure from the impending Tudor conquest, agreed to surrender his Gaelic Royalty to King Henry VIII thus dissolving the Kingdom of Thomond and ending the line of Dalcassian Kings.

This list is supplied in An Leabhar Muimhneach.[28]

Key:

• = Rí Dal gCais
• = Rí Tuadmumu, Rí Mumhan, Ard Rí

Kings of the Dál gCais

Cas Dal gCais Bloid Uí Bhloid Caisín Uí Chaisín #1 Cairtheann Finn Eocach #4 Cormac Coiche #2 Óengus Uí Óengussa #3 Eochaidh Bailldearg Bréanainn Rónáin #5 Conall Caemh Fíonáin #8 Díoma fl. 629 #6 Aedh #7 Forannán #11 Dubh Dúin #10 Ándlidh fl. 697 #9 Feardomhnach Cathal #12 Cearnach Uí Chearnaigh Ailiolla Toirdhealbhach Uí Thoirdhealbhach #13 Torpa died 765 Eichthigheirn Uì Eichthigheirn Mathgamain #15 Fíonachta #14 Domhnall Anluan Maol Tola "Mothla" #16 Cormac Cuircc #17 Reabacán[note 3] died 934 Lachtna #18 Lorcáin #19 Cinnéidigh died 951 976-1014 Brian Bórumha Ua Briain 953-976 Mathgamain 951-953 Lachtna 1014-1063 Donnchad Tadhg 1063-1068 Murchad 1068-1086 Toirdhealbhach 1086 Tadhg 1114-1115 Diarmaid 1086-1114 1115-1119 Muircheartach 1115 Domhnall 1142–1151 1154-1167 Toirdhealbhach 1119-1142 Conchubhar na Cathrach 1143 1151-1154 Tadhg Conchubhar 1168-1194 Domhnall Mór 1167-1168 Muircheartach Muircheartach Diarmaid 1194 Muircheartach Dall 1198-1242 Donnchadh Cairbreach 1198 Conchubhar Ruadh 1242-1268 Conchubhar na Siudane Tadhg Cael Uisce Clann Tadhg 1268-1277 Brian Ruadh Clann Briain 1276-1306 Toirdhealbhach Mór Donnchadh Domhnaill 1306-1311 Donnchadh 1317-1343 Muircheartach 1350–1360 Diarmaid 1311-1313 Diarmaid 1313-1317 Donnchadh 1343-1350 Brian Bán 1360–1369 Mathgamain Maonmhaighe 1375–1398 (claimant) Toirdhealbhach Maol 1369–1400 Brian Sreamhach 1400-1426 Conchubhar 1426–1438 Tadhg an Glemore 1444-1459 Toirdhealbhach Bóg 1438-1444 Mathgamain Dall 1496-1498 Toirdhealbhach Óg 1459-1466 Tadhg an Chomhaid 1466-1496 Conchubhar na Srona 1459-1461 (claimant) Donnchadh 1498-1528 Toirdhealbhach Donn 1528–1539 Conchubhar 1539–1543 Murchadh Carrach Last King of Thomond