Donatus (died ca. 355) was the schismatic bishop of Carthage during the first decades of the Donatist movement.

Little is known of Donatus before 311, when the Christian Church in North Africa was torn by schism. He is reported to have come from Casae Nigrae in Numidia, southwest of Carthage. He may also have engaged in some quasischismatic activity of an "anti-Catholic" sort before coming to Carthage.

The cause of the schism may be said to lie in the persecution of the Church in 303 by the emperor Diocletian. As in the Decian persecution and the Novatian schism that had swept Rome 50 years before, the Church was divided into two camps concerning those who had apostatized under threat of torture or death. The "laxists" sought easy and quick rehabilitation for the lapsed; the "rigorists" held that any act of compromise, even the handing over of the Scriptures to the state (those...