In the time of the Diocletian, one Marinus was sent to Bologna to enforce the emperor's edict.

Enraged at his cruelties, Proculus went to his house and killed Marinus with an axe.

[3] He was himself subsequently beheaded, and the martyr carried his head to the location where a church would later be dedicated to him.

[4] The second account concerns a bishop of Terni, who, attempting to flee persecution from the Goths, came to Bologna where he was subsequently decapitated.

He is depicted in a statue on the spire of the south transept of the Duomo di Milan.