Roman empire,
while it still subsisted, the two emperors, one of whom was on the point of
disappearing, and the whole episcopate, in the most solemn form, should
attest the Roman bishop's universal pastorship. For a great period was
ending, the period of the Graeco-Roman civilisation, from which, after
three centuries of persecution, the Church had obtained recognition. And a
great period was beginning, when the wandering of the nations had prepared
for the Church another task. The first had been to obtain the conversion
of nations linked by the bond of one temporal rule, enjoying the highest
degree of culture and knowledge then existing, but deeply tainted by the
corruption of effete refinement. The second was to exalt rough, sturdy,
barbarian natures, whose bride was the sword and human life their prey,
first to the virtues of the civil state, and next to the higher life of
Christian charity, and thus to link them, who had known only violent
repulsion and perpetual warfare among themselves, in not a temporal but a
spiritual bond. The majestic figure of St. Leo expressed the completion of
the first task. It also symbolises the beneficent power which in the course
of ages will accomplish the second.

The wandering of the nations, says a great historian, was of decisive
effect for the Church, and he quotes another historian's summary
description of it: "It was not the migration of individual nomad hordes, or
masses of adventurous warriors in continuous motion, which produced changes
so mighty. But great, long-settled peoples, with wives and children, with
goods and chattels, deserted their old seats, and sought for themselves in
the far distance a new home. By this the position of individuals, of
communities, of whole peoples, was of necessity completely altered. The old
conditions of possession were dissolved. The existing bonds of society
loosened. The old frontiers of states and lands passed away. As a whole
city is turned into a ruinous heap by an earthquake, so the whole political
system of previous times was overthrown by this massive transmigration. A
new order of things had to be formed corresponding to the wholly altered
circumstances of the nation."[17]

I draw from the same historian[18] an outline of the movement, running
through several centuries, which had this final result. Great troops of
Celts had, before the time of Christ, sought to settle themselves in
Rhoetia and Upper Italy, even as far as Rome. Ci