A musician named Sant Omer or hailing from the Flemish town of Saint-Omer near (the then English town) of Calais is specified as the composer of a three-voice Sanctus in the early fifteenth century music manuscript, Padua, Biblioteca Universitaria, MS 1475.
Fragments of the Sanctus are also found in a manuscript formerly in Budapest,[1] discovered in 1990 but now lost.
The style of the piece has been described as "archaic"[2] with modal rhythms resembling those of the Mass of Tournai.
[4] Adjacent to the Paduan Sanctus is an Agnus Dei in similar style which may be by the same composer.
[5] The Sanctus has been edited and completed by Giulio Cattin and Francesco Facchin in Polyphonic Music of the Fourteenth Century vol.