O'Donoghue of the Glens

The O'Donoghue of the Glens (Ó Donnchadha na nGleann), Prince of Glenflesk, is the hereditary chieftain of his sept of the Kerry Eóganacht. In 1944 his father was one of the few Chiefs of the Name recognized by Edward MacLysaght, the first Chief Herald, as having a verifiable pedigree and entitled to use the title and receive courtesy recognition by the Irish State.

The Eóganacht dynasties ruled the south of Ireland for 500 years or so till the end of the first millennium. According to the Irish origin myths, they descend from Eógan Mór II, son of Ailill Aulom, who was son of Mug Nuadat, (Eógan Mór I), who was supposed to have lived some time in the 2nd century. Over the years, various septs of the Eóganacht branched off and some faded into insignificance. The O'Donoghue of the Glens is one of the Eóganacht lineages which remain to this day with an acknowledged Chief.

According to tradition, The O'Donoghue Mór and The O'Donoghue of the Glens descend from sons of Auliffe Mór O'Donoghue (d. 1158), Cathal and a younger son Conchobar, respectively (though Y-DNA evidence suggests they are of different lineages). Auliffe Mór's dynasty is that of the Cinel Laegarie of Eóganacht Raithlind/Uí Echach Muman, whose original territory was in West Cork prior to the time of Brian Boru, after which they invaded and secured the kingdom of the Eóganacht Locha Léin, displacing the Loch Lein O'Moriarty's and O'Carrolls.

There was much internecine war during the time of Auliffe Mór, when the O'Brien dynasty of Thomond were battling (ultimately unsuccessfully) for control of all Munster. The O'Briens were pressuring the Eóganacht from the north and the east, forcing them southwest into Kerry. The Cashel O'Donoghues, by then pressured by their Eóganacht cousins, the increasingly powerful MacCarthy dynasty, would surely have been amongst them.

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