INTRODUCTION TO SOCIOLOGY 671
and inhabited in very large part by people of Romance tongue. This was to be the point of departure for all the later attempts to establish an intermediate zone between Germany and Gaul. For the moment this zone was still an integral part of the Lotharin- gian kingdom, but it was soon to form the kingdoms of Lorraine and of Aries or Burgundy, which, long united to the Germanic empire, was to incline toward separation from it. Intermediate zones form a stage in the evolution of frontiers. They are estab- lished between states which are independent, fortified, or even hostile, and they introduce into their reciprocal relations an ele- ment favorable to the maintenance of peace. They are buffers destined to soften conflicts; but, unfortunately, they are also destined, in a period essentially military, to serve as the field of battle for great states. Later, a system of neutrality for the inter- mediate states was to coincide with fresh attempts at a political equilibration attempts, however, always precarious, so long as the internal equilibration of the states should not permit the estab- lishment of a peaceful civilization founded no longer upon merely political, but upon really social, changes.
The unity of the Carolingian empire was again re-established for a moment by Charles the Fat, who from 876 to 887, the year when he was deposed by his subjects, either inherited or took pos- session by fraud or violence of all the territories situated outside of his own kingdom. But the empire, after his reign, was again dismembered into five kingdoms ; France was formed once more within the limits of the treaty of Verdun, and the kingdom of Germany expanded toward the west.
While political sovereignty tended continually, under the feudal regime, to follow the same course as feudal proprietorship, now expanding and now being divided up, and continually erect- ing frontiers which were no sooner fixed than removed, and yet submitting Europe to a really uniform regime within a true com- mon structure, the Roman church, which was also a political state, with political frontiers bounding the domains of the papacy, spread over almost all the old Empire of the West, even into Ire- land, Germany, Bohemia, and Moravia. It passed even the military marches which were established beyond the Elbe; the
