Célidoine a French prelate, was bishop of Besanon after Leonce, about 443. Hilary, bishop of Arles, had deposed him for various offences, among others, for. having married a widow and having assisted at a service before being ordained; but Celidoine appealed to pope Leo I, who ordered him to be re- established in his see. This is the first time that a bishop made an appeal to a pope; but Hilary did not acquiesce in the decision, and Celidoine remained deposed. It is supposed that Celidoine perished in 451, during the capture of Besancon by Attila. See Hoefer, Nouv. Biog. Générale, s.v.