Marsus

Saint Marsus was a missionary and bishop, venerated in Gaul and in Saxony. The French sources place him not in the third century but later, toward the fifth.

According to the testimonies, he was ordained priest at Rome by Pope Sixtus III and sent, with Saint Peregrinus, to Gaul, together with the deacon Corcodemus, a subdeacon, Jovian, and a reader of the same name, to preach the Gospel and strengthen the faith of the believers. The group settled in the region around Auxerre and won many inhabitants to Christianity. Peregrinus is said to have made Marsus a bishop and then to have gone to an island inhabited by pagans, where he died a martyr. Marsus himself died after many trials, on 8 June or 4 October, and was buried at Auxerre. He was reckoned a saint with the title of "confessor".

Almost forgotten today, in the early Middle Ages he was a much venerated saint. Altfrid, bishop of Hildesheim and founder of the diocese of Essen, brought the saint's relics from Auxerre in 864. Between 999 and 1002, with the help of Otto III and of Hugh of Chalon, bishop of Auxerre, his skull and sternum reached the diocese of Essen. In the fifteenth century the skull was placed in a reliquary in the form of a bust, in the treasury of Essen cathedral, lost when the treasury was evacuated in the Second World War. At Auxerre a church has been dedicated to him since the 1960s.

His commemoration is kept on 4 October in the Western calendar. He is a saint of the undivided Church, honoured without synodal canonization.