Dictionary of National Biography, 1885-1900/O'Hartagain, Cineth
O'HARTAGAIN, CINETH (d. 975), Irish poet, was a native of the north of Ireland, and his death is recorded by Tighearnach under the year 975. A poem on the former grandeur and present desolation of Tara, beginning 'Domhan duthain alainne' ('Transitory, beautiful World'), is attributed to him in the 'Leabhar Gabhala' of the O'Clerys. Several long poems ascribed to him occur in the 'Dinnsenchus,' a work which relates the legendary history of the duns, lakes, plains, mountains, and other topographical features of Ireland. It gives a prose account of each place, followed by an account in verse.
[Book of Leinster, facsimile; Book of Ballymote, photograph; Transactions of Iberno-Celtic Society, Dublin, 1820.]