The town was several times plundered by the Danes in the 9th century; it was laid waste by Dermot O'Brien in 1071, and was burned in 1137.
The Conquest of Ireland was republished in 1892 by Goddard Henry Orpen, under the title of The Song of Dermot and the Earl (Oxford, Clarendon Press).
For Irish affairs the Song of Dermot (ed.
Dermot abducted the wife of 0 Ruairc more with the object of injuring his rival than from any love of the lady.
The injured husband called to his aid Roderic, the high king (airdrigh) of Connaught; and in 1166 Dermot fled before this powerful coalition to invoke the aid of England.
A licence to enlist allies among the Welsh marchers, Dermot secured the aid of the Clares and Geraldines.
To Richard Strongbow, earl of Pembroke and head of the house of Clare, Dermot gave his daughter Eva in marriage;.
The historical importance of Dermot lies in the fact that he was the means of introducing the English into Ireland.
See The Song of Dermot and the Earl, an old French Poem (by M.
Dermot MacMorrough, king of Leinster, an unquiet Irish prince who for good reasons had been expelled by his neighbors, came to Henrys court in Normandy, proffering his allegiance in return for restoration to his lost dominions.
He could not spare attention for the matter, but gave Dermot leave to enlist auxiliaries among the turbulent barons of the South Welsh Marches.
Dermot was triumphant, and sent for more auxiliaries, Ispiring to evict Roderic OConnor of Connaught from the precarious throne of High King of Ireland.
Early in the next spring Dermot iied, and Earl Richard, in virtue of his marriage, claimed the kingship of Leinster.