The Roman Empire made great efforts in the Christianization process as to replace Roman traditional religions with Catholic Christianity and to suppress heresy and schism in order to reshape its subjects' national religious identity and to maintain social harmony and local stability. The North African Catholic church actively participated in the religious affairs of the Empire, giving their strongest support to the construction of such an unified identity, sharply criticizing the localized religious identity of the Donatists. Augustine used the unity of the Catholic church and the national religious identity promoted by the Roman Empire to criticize the Donatists' localized religious identity and argued for the priority of Catholic faith by means of his theory of the two cities. With a continued reflection on the fall of Rome in 410, Augustine abandoned the early Christian political theology represented by Eusebius, as he argued that Christians' identity should be eternal and transcendental, and not be restrained by time or by an earthly state.