Mercurialis of Forlì was a 4th-century Christian bishop and presbyter who served the community in Romagna. Living during a period of significant religious transition, he participated in the Council of Rimini in 359. He was recognized for his firm opposition to both Arianism and paganism. Although historical records place him in the late fourth century, local traditions have associated him with the Apostolic Age, claiming he was the first bishop of his see.