O'Ciaran or O'Kieran is given as a chief of Fearnmuigh as a clan of Tír Eoghain. The O'Larkin sept is cited as chiefs alongside the O'Neills and MacCanns in the old territory of Airgíalla (Oriel), where they were chiefs of Farney and West Uí Breasail (in County Armagh). O Cosgro (ve) (O Cosgraigh) was the name of the chiefs of Feara Ruis (Fir Rois) near Carrickmacross and Ardee. MacArdle, a branch of the MacMahons of Oriel are noted here, as well as septs of Callan, O'Finn, O'Larkin, Hughes/Hayes, and O'Donegan.
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