Donatism was the heresy propagated first by Donatus, a bishop of Carthage (313-355), who led a protest against Catholic practices. Donatist charges centered on the fact that certain Catholic bishops had handed over the Scriptures to be burned during the early third-century persecution under Diocletian. Such an act, the Donatists insisted, was a serious sin of apostasy. Since the Catholic pastors were ordained by bishops who had sinned so grievously, the Donatists believed they, rather than the Catholics, constituted the true Church of Christ. They argued that the validity of the sacrament depends upon the moral standing of the minister. the Donatists (so named after their leader Donatus) split away from the Catholic Church of North Africa because of the election of Caecilian as bishop of Carthage. The Donatists believed that Caecilian's ordination was invalid because one of his consecrators had been a traditor, one of those who surrendered copies of the sacred scriptures during the great persecution. Like Cyprian, the Donatists believed that the validity of the sacrament depended upon the holiness of the celebrant. The Donatists were opposed to state interference in church affairs and the secularization of the church. Despite persecution (317-321) and the Vandal invasion of 429, Donatism survived into the seventh century in North Africa, when it and Catholicism were overcome by Islam. Christianity effectively became extinct in North Africa during the course of the seventh century. Nonetheless, Augustine became Donatisms's chief rival, and his writings remained highly influential in the fight to erradicate the heresy.