The composer known only as Guido by virtue of three pieces contained in the Chantilly Codex is most probably a cleric from the name of Guido de Lange. Guido 1st turns up inside a 1363 record identifying himself like a rector in diocese of Rouen, and additional documents determine Guido with Archbishop Guillaime de la Jugée, who passed away in 1376 and whose tomb still stands in the cathedral of Narbonne. Nevertheless, by this time around, Guido has already been defined as a cantor in the papal chapel at Avignon. It’s possible that Guido was among the old composers who added to the items in the Chantilly manuscript, the written text of his Rondeaux Dieux gart qui bien chantera pokes fun in the unconventional varieties of music used in the Avignon courtroom. Guido isn’t heard of once again following the 1370s, and in 1378 the fantastic schism started between Pope and Anti-Pope. Guido de Lange isn’t puzzled with Guido frater, a fourteenth hundred years theorist who non-etheless belongs to a youthful era.