Nationalism of Rome's subjects
"Besides this great rift in the empire separating the Latin West from the Hellenic East, there were other lines of cleavage which followed, in the main, the old boundaries of the tribes or nations that Rome had subjugated. It was the still unsubdued national spirit in Spain and Gaul and Britain, and among the Germans and the Jews, that, for one thing, made necessary the change of the republic into the military empire. This national spirit was not so strong in the later days of the empire as it was in the earlier; yet it was by no means everywhere dead. Even where it had practically died out, there had not yet sprung up to take its place a feeling of attachment for the empire. Thus, for instance, as the historian Stephens says, "Gaul ceased to be a nation without becoming in sentiment or spirit an integral member of the empire. . . . Gaul therefore fell an easy prey to her German invaders."8"
Rome, Its Rise and Fall By Philip Van Ness Myers 1901