Le Roi d’Ys is based on an ancient Breton legend; even the choice of a subject based on legend illustrates the ideological link between Lalo’s opera and the Wagnerianism so prevalent throughout Europe at the time. Lalo furthermore made use of various elements of popular music inspired by Breton folklore that give the entire score a special character and flavour. Another link to Wagner lies in his use of leitmotifs associated with each of the principal characters (Rozenn, Karnac, and Margared), though Lalo is quite prudent in his use of these. Even so, Le Roi d’Ys certainly remains a profoundly and decidedly French opera in all of its main features. Blau’s libretto has the virtue of being “simple, clear, uncluttered by historical complications, easy to understand, and sufficiently rich in dramatic strands”, in the words of Lalo’s first biographer Georges Servires in his brief though pithy monograph on the composer.