It is important to distinguish between the universalist and localist conceptions of the empire, which remain controversial among historians. According to the former, the empire was a universal monarchy, a "commonwealth of the whole world, whose sublime unity transcended every minor distinction"; and the emperor "was entitled to the obedience of Christendom". According to the latter, the emperor had no ambition for universal dominion; his realm was limited in the same way as that of every other ruler, and when he made more far-reaching claims his object was normally to ward off the attacks either of the Pope or of the Byzantine emperor. According to this view, also, the origin of the empire is to be explained by specific local circumstances rather than by overarching theories.