The text of the following story, now for the first time printed, is taken from a transcript which I made in 1871 from the only known copy, that, namely, in columns 391–395 of H. 2. 16, a manuscript of the fourteenth century preserved in the library of Trinity College, Dublin, and commonly called the Yellow Book of Lecan. The story is one of a class of sagas called Imrama, of which only three other specimens are known to exist, and on which Dr. Schirmer of St Gallen is about to publish a treatise. Like the best known of these sagas, the Imrom Maele Duin, our story is twofold, each part of it being first told in prose and then in verse, which is full, as usual, of chevilles, is often obscure, and is sometimes obviously corrupt. In the present edition the verse is omitted.
The Voyage of Snedgus and Mac Riagla (or Mac Riaguil) has been analysed by O'Curry in his Lectures, p. 333, and is quoted by him in his Manners and Customs III, 385, as giving two instances of the rare word sianan, some kind of vocal music. Other such words are cuilefaid=culebad (gl. flabellum)1; fant 'hollow', borrowed from the Welsh pant; comgaire 'vicinity'; braga (dat. pl. braigtib) 'prisoner'; aile 'fence'; mesrugud 'adjudication'; forbas 'siege'; eisles 'neglect'. The phrase dia bliadna, literally '(that) day of (the following) year', and the act. redupl. future pl. 3 gébtait may also be noted.
Some of the persons named in our tale are historical characters of the seventh century. King Domnall son of Aed, son of S. Colomb cille's first cousin Ainmire, died A.D. 642 (or 639 according to the Four Masters). His successors, Maelcoba's sons, Conall Cael and Cellach, reigned jointly till A.D. 659 (or 656). The middle of the seventh century may therefore be fixed roughly as the date of incidents of the tale.
The Men of Ross, whose vengeful act gives rise to the story, were a tribe whose territory (according to O'Donovan2) ‘comprised the parishes of Carrickmacross and Clonany, in the county of Monaghan, and parts of the adjoining counties of Meath and Louth.’