Eóganachta

The Eóganachta (Modern , ) were an Irish dynasty centred on Cashel which dominated southern Ireland (namely the Kingdom of Munster) from the 6/7th to the 10th centuries, and following that, in a restricted form, the Kingdom of Desmond, and its offshoot Carbery, to the late 16th century. By tradition the dynasty was founded by Conall Corc but named after his ancestor Éogan, the firstborn son of the semi-mythological 3rd-century king Ailill Aulom. This dynastic clan-name, for it was never in any sense a 'surname,' should more accurately be restricted to those branches of the royal house which descended from Conall Corc, who established Cashel as his royal seat in the late 5th century.

==High Kingship issue== Although the Eóganachta were powerful in Munster, they never provided Ireland with a High King. Serious challenges to the Uí Néill were however presented by Cathal mac Finguine and Feidlimid mac Cremthanin. They were not widely recognized as High Kings or Kings of Tara, as they did not belong to the Uí Néill, but they controlled territories as large or larger than those of the other dynasty. The kings of the Hill of Tara were sometimes called High Kings but were not recognized as kings of all Ireland in the historical period. However, this is to put the supposed position of "High King of Ireland" on a platform that it probably never enjoyed. The social structure of Gaelic Ireland was extremely complex, hierarchically oriented and aristocratic in concept. At the summit of society stood the king of a province, variously styled in the law texts as "King of great kings" (), "Chief of kings" () and "The ultimate king of every individual" (). From his justice there was no appeal, nor did the Brehon Law acknowledge the existence of the High Kingship of Ireland. The ri ruirech had no legal superior. In Munster this legal theory was explicitly adhered to by the annalists who styled the provincial kings as "High King" (), thereby stressing his absolute sovereignty. As the concept of the High Kingship of Ireland was developed from the 9th century onwards by the Uí Néill clan, the kings of Munster counterbalanced that historically inaccurate doctrine by stressing their alternative right to that title, or instead the enjoyment of full sovereignty in Leth Mogha, that part of Ireland south of a line from Dublin to Galway.