Conaille Muirtheimne had once formed part of the over-kingdom of the Ulaid, and it remained an ally of the Ulaid for the greater part of its history. This is set out in Lebor na gCeart (the Book of Rights) in which the Conaille are listed among "The Territories whose King paid Tribute to the Ulaidh." In return, the King of Ulaidh owed to "The Heroic King of Muirthemhne - six round goblets full of ale, ten ships from the Hero of Elga, ten steeds and ten brights cloaks."
Its people are sometimes thought to be Cruthin, the name used by the Irish for the Picts. Dubhaltach MacFhirbhisigh stated of them: "To the Cruithne of Ireland belong the Dal Araidhe, the seven Laighsi of Leinster, the seven Soghain of Éire, and every Conaill of Eirinn." For much of its history it was at war with the Oirghialla and the Uí Néill; sometimes even with its Ulaidh allies.
The last recorded king of Conaille Muirthemhne died in 1081, yet in 1107 Fergus, son of the King of Conaille, was killed in battle by the Uí Breasil Macha", so it seems the kingdom still retained independence. However, the Orgialla seem to have brought it under their control sometime after this, most probably c. 1130 by Donnchad Ua Cerbaill, king of Airgialla, and it was incorporated into his kingdom.
In 1153 when High King Domhnall Mac Lochlainn " ... plundered ... and burned Conaille."
Eoin MacNeill held the Conaille Muirtheimne to be kin of Ulaid and Érainn, descending from Conall Anglonnach, a son of Dedu mac Sin (MacNeill, pp. 97–8). Their association with the Cruthin appears to be the end result of a series of later inventions.
Geographical description of the kingdom
This description of Conaille Muirtheimne is taken from the article cited below:
- "Until it fell under the control of the O'Carrols in the twelfth century, what is now County Louth was divided between three minor kingdoms. In the south lay that of Fir Arda Ciannacht (whence Ferrard); ... In the east and centre of the present county was the Airgiallan kingdom of Fir Roise, and in the north was that of the Conaille Muirtheimne ... The territory of Conaille Muirtheimne was associated with Mag Muirtheimne, 'the Plain of Muirtheimne' ...the core area of the kingdom appears to have been roughly equivalent to the barony of Dundalk Upper plus the parish of Dromiskin. The regions to the south-west (Louth) and north-east (Cuailgne), i.e., Cooley, were of uncertain or perhaps fluctuating status."
Kings of Conaille Muirtheimne 688-1107
- Uarcraide ua Osseni, d. 688
- Amalgaid mac Cathasaig, d. 741
- Fagall (Fallach) Finn mac Oengusa, d. 743
- Foidmenn mac Fallaig/Fallomain, d. 752
- Uargal (Uargalach) mac Uachtbrain, d. 765
- Sluagadach mac Uargalaig, d. 789
- Fiachain, d. 792
- Spelan mac Sluagadaig, d. 824
- Mael Brigte mac Spelain, d. 869
- Gairbith mac Mail Brigte, d. 878
- Ciblechan mac Mail Brigte, d. 890
- Mael Morda mac Gairbitha, d. 891
- Conglach mac Gairbitha, d. 913
- Dommnall mac Gairbitha, d. 914
- Mael Brigte mac Ciblechain, d. 914
- Spelan mac Congalaig, d. 923
- Crongilla mac Cuilennain, d. 937
- Mac Etig mac Cuilennain, d. 951
- Cinaed mac Crongilla, d. 970
- Congalach mac Meic Etig, d. 988
- Matudan mac Cinaeda, d. 996
- Gilla Crist ua Cuilennain, d. 999
- Muiredach, d. 1005
- In Gercce, d. 1005
- Crinan mac Gormlada, d. 1012
- Cinaed mac In Geircce, d. 1029
- Domnall mac Gilla Christ, d. 1052
- Cinaed mac meic Odormaic, d. 1066
- Mac Ui Threodain, d. 1078
- Mac In Geircce, d. 1081
- Unnamed King of Conaille, alive 1107.
- Eoin MacNeill (1911). C. "Early Irish Population Groups: their nomenclature, classification and chronology"". Proceedings of the Royal Irish Academy 29: 59–114.
- David E. Thornton (1997). "Early Medieval Louth: The Kingdom of Conaille Muirtheimne" (digital document). Journal of the County Louth Archaeological and Historical Society (County Louth Archaeological and History Society) 24 (1): 139–150. JSTOR 27729814.
- "Conaille-Muirthemhne" in Feilscribhin Eoin O'Neill, Dublin, 1940.