It may not be improper here, to give the story which is the foundation of this poem, as it is handed down by tradition. Usnoth, lord of Etha, which is probably that part of Argyleshire which is near Loch Eta, an arm of the sea in Lorn, had three sons, Nathos, Althos, and Ardan, by Slissáma, the daughter of Semo, and sister to the celebrated Cuthullin. The three brothers, when very young, were sent over to Ireland, by their father, to learn the use of arms, under their uncle, Cuthullin, who made a great figure in that kingdom. They were just landed in Ulster when the news of Cuthullin's death arrived. Nathos, though very young, took the command of Cuthullin's army, made head against Cairbar the usurper, and defeated him in several battles. Cairbar at last having found means to murder Cormac the lawful king, the army of Nathos shifted sides, and he himself was obliged to return to Ulster, in order to pass over into Scotland.
Dar-thula, the daughter of Colla, with whom Cairbar was in love, resided, at that time, in Selâma, a castle in Ulster: she saw, fell in love, and fled with Nathos; but a storm rising at sea, they were unfortunately driven back on that part of the coast of Ulster where Cairbar was encamped with his army. The three brothers, after having defended themselves, for some time, with great bravery, were overpowered and slain, and the unfortunate Dar-thula killed herself upon the body of her beloved Nathos.
The poem opens, on the night preceding the death of the sons of Usnoth, and brings in, by way of episode, what passed before. It relates the death of Dar-thula differently from tho common tradition; this account is the most probable, as suicide seems to have been unknown in those early times: for no traces of it are found in the old poetry.
