Rosc

Liam Breatnach observed in an important article (Breatnach 1984, with references) that 'Old Irish texts appear in three forms: prose, rhyming syllabic verse, and rosc. The simplest definition of rosc is that it is neither of the other two.'

Elsewhere we find descriptions of the most archaic Irish poetry, the passages of obscure poetry called rosc. Sigerson analyzes rosc as rhythmical though unrhymed verse designed to express or to stir up vehement enthusiasm and claims it is the first example of blank verse (Bards of the Gael and Gall 25); Hull characterizes rosc as a declamatory, alliterative blank verse where changes of meter correspond to changes of idea (Text Book I: 202-4).

Likewise, the 'Cauldron of poesy' and 'Bretha Déin Chécht' both contain prose, rosc, and rhyming syllabic verse.

Until the last few decades, however, many of the roscada were interpreted as prose, but recent scholarship has suggested that most, if not all, are poems composed according to archaic metrical principles that had been largely superseded by the eighth century.