The study of medieval religion is of primary importance alike for those who wish to know something of the history of Christianity and for those who wish to know something of the history of Europe. We cannot understand the religious problems of the world today unless we understand something of their roots in the history of the past, and we cannot understand the secular history of modern Europe unless we understand something of that long thousand-year process of change and growth which we name the middle Ages. Those thousand years saw the making of Europe and the birth and rebirth of 'Western culture: they also witnessed the creation of that socio-religious unity that we call Christendom, and the gradual penetration of our culture by Christian belief and Christian moral and scholarly standards. They have left an indelible imprint on both our social and religious life. They have helped to make us what we are, whether for or evil, and even those who know and care nothing about medieval religion and culture are themselves the unconscious heirs of medieval tradition.
The differentiated sociological structure that was the main distinguishing factor between the barbarian kingdoms and the old aristocratic society did have its effect upon the Church. The Church of the Empire had been a Church of the cities. Its organization was dependant upon the municipal system, and the bishop played an even more vital part in the life of the city than the civil magistrates themselves. The larger the city', the greater, as a rule, was its ecclesiastical importance. Among the Germanic and Celtic peoples, however, social conditions were entirely different. City life was non-existent, and the only units were the people or the tribes and their subdivisions.
Here, the Church could find no fixed centres on which to concentrate its action and from which to radiate its influence; hence, forcing either to create such cent res there itself through the foundation of monasteries which in the Celtic countries became the basis of the whole ecclesiastical organization, or else to make the tribal territory' or petty kingdom itself an Episcopal see as we find in many cases, in Anglo-Saxon England.
In the Frankish kingdom, where the city and the city territories survived, the Church was able to preserve its old basis of organization, but even here the decay of urban life and the disappearance of the old territorial organization destroyed the cohesion and autonomy of the hierarchy and brought them into dependence on the kingly power. The Church became more and more closely bound up with the life of the State. It ceased to be simply a province of the international Christian society and became a territorial Church (or what the Germans call a Landeskirche). This development was not, however, entirely due to the growing dependence of the Church upon the State: it also involved a corresponding dependence of the Stare upon the Church. The trained bureaucracy, the strength of the later Roman Empire, no longer existed; and the clergy was the only ...