An elaborate polyphonic Mass to be celebrated in honour of St Maurice arguably makes sense nowhere else in Europe than in Savoy at this period. (It may be noted in passing that the saint was important for René d’Anjou as well, and is famously depicted in a background sacra conversazione
in an altarpiece painted for René by Nicolas Froment in order to to be offered to the Carmelite convent at Aix-en-Provence, where it remained until the Revolution.) The music for such a celebration was in all probability written with the Order of St Maurice in mind, thus on commission from Savoy. But it has also been suggested, by Alejandro Planchart, that this could well have happened in the later 1440s, while Dufay was still resident in Cambrai but evidently very much in contact with his Savoyard patrons (and indeed would travel through the Duchy as far as Turin in the late spring of 1450 on his way into Italy with a group of singers, perhaps bound for Padua). In the Proper movements for St Maurice Dufay paraphrases the relevant chants in the cantus with a beautiful, unobtrusive melodic and rhythmic control, underpinning this wide-spanned top part with two skilfully contrived tenor parts (three in the Offertory, and one in some duo sections). These lower voices, working together in tandem within broadly the same range, extend and colour the modal-harmonic field of the cantus and help to give it direction, intensity and cadential force.
from notes by Philip Weller © 2009