The coexistence of such states demanded in its turn the general acceptance of certain common moral ties and standards among a group of neighboring peoples; and such a tie was furnished by the religious bond with which Catholic Christianity united the peoples of Western Europe--a bond whereby the disorder and anarchy of the early Middle Ages was converted into a vehicle of political and social education.

The members of the Christian body had much to fear from their fellow-Christians, but they also had much to gain.

They shared many interesting and vital subjects of consultation; and even when they fought, as they usually did, they were likely to fight to some purpose.
But beyond their quarrels Catholic Christians comprised one universe of discourse.

They were somehow responsible one to another; and their mutual ties and responsibilities were most clearly demonstrated whenever a peculiarly unscrupulous and insistent attempt was made to violate them.

As new and comparatively strong states began to emerge from the confusion of the early Middle Ages, it was soon found that under the new conditions states which were vigorous enough to establish internal peace and to protect their frontiers were not vigorous enough to conquer their neighbors.