The story of the combat between father and son has touched almost every nation which has produced an epic, or ballads of an epic character, or as in the case of the Irish, epic tales. That particular version of the story, which in Old-Irish literature is embodied in the tale of the fight between Cúchulinn and his son ConlaThe oldest form of the name is Conle; in later and modern texts, it has been made into Conlaoch. is ultimately derived, both in its main features and in all important details, from the Persian story of Rustem and Sohrab. This occurs in an episode in the of Firdausi, a poet of the tenth century, who worked up older legends. Long before his time, however, it had found its way from Persia westward. It must have reached the Goths in their migrations, from whom it passed into the literature of several older Germanic tribes. For the Old-High-German poem of the combat between Hildebrand and Hadubrand has a Low-German origin; we meet the same motive in the Norse Thidrek-saga, and find traces of it in Anglo-Saxon literature. It seems most likely that it was the Anglo-Saxons who handed it on to the Irish some time during the seventh or early eighth century.

In Old-Irish literature the legend was naturally incorporated in the chief cycle of story-telling at that time, attaching itself to the hero whose adventures most resembled those of Hildebrand. Like Rustem and Hildebrand, Cúchulinn had spent his youth in foreign lands. There he begot the son who was to fall by his hand.

The discovery of another Irish setting belonging to the Ossianic cycle will cause little surprise to those who know that this later cycle modelled many of its stories on those of the older heroic cycle. It is true, the legend of Finn and Oisín did not lend itself well to the introduction of the new motive. For in all the stories of the cycle Finn and his son are throughout on amicable terms and closely associated in their exploits and adventures. We shall see how the narrator gets out of the difficulty by inventing a quarrel between Finn and Oisín, during which the latter absents himself for a whole year. Again, the tragic issue was not adaptable to the Ossianic saga. So a humorous and burlesque treatment is substituted, such as we find occasionally in the literature of other nations who have introduced the motive. Here the combat is merely a bit of rough horse-play or wrangle of words. This is the case, e.g., in a thirteenth-century French epic called , in which a peasant returning home at the close of a war meets his two sons walking along with their backs bent under a heavy load of wood. He does not recognize them, they behave rudely to him, and a quarrel of words ensues, in the course of which recognition is brought about.See M. A. Potter's (Grimm Library, vol. 14), p. 82; and Alfred Nutt's (International Folklore Congress, 1891), p. 128. This is the form chosen by the Irish story-teller.

The poem has come down to us, so far as I know, in three manuscripts only: H i.e. Harleian 5280, fo. 35b1; N i.e. 23 N 10, p. 53; and M i.e. Ewen McLachlan's transcript which he called Leabhar Caol, preserved in the Advocates' Library Collection of Gaelic MSS., vol. 83, p. 251. The vellum manuscript itself from which M'Lachlan made his transcript has for some time been missing from the Library. It was called Leabhar Cille Brighde, and bore the number 32. An account of its chief contents will be found in the , Edinburgh 1805.Reprinted in the , vol. 5, p. 130. ^{(The Report is available online on www.archive.org.)} As appears from a colophon at the end of our piece, the scribe who wrote it was called Fithel mac Flaithrig mic Aedha.Misi Fithel mac Flaithrig mic Aodho. Finit. I am indebted to the kindness of Professor Donald Mackinnon for a most careful copy of M'Lachlan's transcript.

Though none of these three MSS. is earlier than the sixteenth century, the language both of the prose and poetry contained in the piece is pure Old Irish. Indeed, we have here another instance of an Ossianic text which may be confidently assigned to the ninth century. Short as both prose and poetry are—the latter only sixteen stanzas—there are enough old forms, particularly in the verb, that make it impossible to assign a later date. In syntax the position of the attribute before the noun on which it depends may be noted, as in fóibur frossae, aiss lomma. Unfortunately, the verses are badly handed down in all the MSS., being defective and corrupt in several places. My translation can therefore only be tentative and imperfect.