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mon organization, which was very striking, for example, in the case of the Mussulmans and the Christians at the time of the Crusades.
During almost all of this period political sovereignties were demesnial properties which had their frontiers just as all estates have their boundaries ; they expanded or shrunk like other estates through fraudulent or violent occupation, by purchase or sale, through marriage, inheritance, or partition. All the surplus of social superstructure modeled itself upon this demesnial organiza- tion, as well as Christianity itself, whose primitive tendencies had been toward equality. External frontiers are always related to internal inequalities, upon which the principle of sovereignty in reality rests; they also represent existing inequalities between different societies. They arise or decline according to the establish- ment of regular and peaceful relationships, and they are restrained or developed as they prevent or favor the leveling of intersocial conditions and their integration into a common existence.
In the first century almost all the Christian churches were in the East, with the exception of those of Rome and Pozzuoli ; the Jews figured in large numbers in them. Christianity, however, was not a unilateral development of Judaism, and as it grew it was augmented by the theological and philosophical tributaries of all the beliefs and doctrines which, relative to the existing con- ditions, were the best adapted to their environment. Already in the second century Christianity developed in Asia, in Greece, in Italy, and gained a foothold in Gaul and in Africa. In the third, it continued to spread where it had already been introduced, and it penetrated into Spain, especially into Batica, which was the part most Romanized; in the fourth, it established itself in the center of the Balkan peninsula.
In proportion as it spread it became definite and organized. At the Council of Carthage in 258 there were eighty-one bishops from Africa. About the year 400 there were bishops in every Roman province, and their bishoprics did not correspond with the divisions of the empire. About the year 324 the frontiers of the latter were crossed ; there was a bishop of the Goths, and another of the Cimmerian Bosphorus. In short, the religious
