[1] Marianus originated in the area of Bourges, but, driven out by invading Goths, took refuge in the Abbey of Saints Cosmas and Damian in Auxerre, later the Abbey of St. Marianus, in the time of Saint Mamertinus, then abbot.
He made outstanding progress in the monastic life but the abbot sent him to the monastery's estate in Mézilles ("Meziclis"),[2] where the present parish church is dedicated to him,[3] to look after the livestock.
He made a great success of this, and also gained the trust of the wild creatures in the surrounding forest.
Marianus is a protector of animals against diseases and attacks by wolves, snakes and so forth.
At Mézilles there is an annual pilgrimage involving the blessing of animals in the church and at the nearby fountain.