It is generally admitted that this period begins with the pontificate of Gregory the Great, 590, and ends with the Reformation in the early part of the sixteenth century. But before entering on the general history, we will endeavor to answer a question which has been asked, and which, we doubt not, is on the minds of many: When, and by what means, did the power fall into the hands of the Roman pontiffs, which led to their supremacy and despotism during the middle ages? The question is an interesting one, but to answer it fully would lead us beyond our limits. We can only point out a few facts in the chain of events which laid the foundation of the great power and sovereignty of the See of Rome.
From the time of the famous edict of Milan in 313 the history of the church changes in its character. She then passed from a condition of distress and persecution to the summit of worldly prosperity and honor: other questions besides those of Christianity were henceforth involved in her history. Having entered into an alliance with the State, her future path was necessarily formed by her new relations. She could no longer act simply in the name of the Lord Jesus, and according to His holy word. But complete amalgamation there could never be. The one was from heaven, and the other of this world. They are, in nature, opposed to each other. Either the church aspired to be the mistress of the State, or the State encroached on the province of the church and disregarded her inherent rights. This was exactly what took place. Soon after the death of Constantine the struggle between these two great powers, the church and the State, for the government of the world, commenced; and, in order to ensure success in this warfare, the Roman pontiffs had recourse to ways and means which we will not characterize here, as they will come before us in due course.
Before Constantine transferred the seat of empire to Byzantium and built Constantinople, Rome was the acknowledged metropolis, and her bishop the primate. But when Constantinople became the imperial city, her bishop was raised to the rank of patriarch, and soon began to lay claim to the dignity of the Roman pontiffs. This was the commencement of the Greek church as a separate communion, and of the long contest between the East and the West. There were now four patriarchs, according to the plan of the Emperor, Rome, Constantinople, Antioch, and Alexandria. The rank of the bishop was governed by the superiority of the city in which he presided; and as Constantinople was now the capital of the world, her bishops would yield to none in honor and magnificence. The others were jealous, Rome complained, the strife began, the breach widened; but Rome never rested until she had gained the ascendency over her feeble and less ambitious rival.