*The primacy of Rome.* In the third century, a movement took place for the organization of the separate churches in larger unions, and in this way the provincial synods arose. In these the metropolitan bishops, that is, those from the provincial administrative centers, assumed the leadership. Among the churches of the empire as a whole two rival tendencies made themselves manifest. The one was to accord equal authority to all the bishops, the other to recognize the supremacy of the bishop of Rome. The claim for the primacy of the Roman see was based upon the imperial political status of Rome, and the special history of the Roman church. It was strongly pressed by certain bishops of the second century who laid emphasis upon the claim of the Roman bishopric to have been established by the Apostle Peter. PART IV THE AUTOCRACY OR LATE EMPIRE: 285–565 A. D. CHAPTER XXI FROM DIOCLETIAN TO THEODOSIUS THE GREAT; THE INTEGRITY OF THE EMPIRE MAINTAINED; 285–395 A. D. I. DIOCLETIAN: 285–305 A. D. *The epoch-making character of Diocletian’s reign.* Upon Diocletian devolved the task of bringing order out of chaos, of rebuilding the shattered fabric of the Roman empire, of reëstablishing the civil administration and taking effective measures to secure an enduring peace. Like many of the emperors of the third century, Diocletian was an Illyrian of humble origin who by sheer ability and force of character had won his way up from the ranks to the imperial throne. In attacking the problem of imperial restoration he displayed restless energy and versatility, a thorough-going radicalism which knew little respect for traditions, and a supreme confidence in his ability to restore the economic welfare of the empire by legislative means. In his administrative reforms he gave expression to the tendencies which had been at work in the later principate and with him begins the period of undisguised autocracy, in which the emperor, supported by the army and the bureaucracy, is the sole source of authority in the state. Like Augustus, Diocletian was the founder of a new régime; one in which the absolutist ideal of Julius Caesar finally attained realization.