Charlemagne's son, Louis the Pious, who became emperor in 814 A.D., was a well-meaning but feeble ruler, better fitted for the quiet life of a monastery than for the throne. He could not control his rebellious sons, who, even during his lifetime, fought bitterly over their inheritance. The unnatural strife, which continued after his death, was temporarily settled by a treaty concluded at the city of Verdun. According to its terms Lothair, the eldest brother, received Italy and the imperial title, together with a narrow stretch of land along the valleys of the Rhine and the Rhone, between the North Sea and the Mediterranean. Louis and Charles, the other brothers, received kingdoms lying to the east and west, respectively, of Lothair's territory. The Treaty of Verdun may be said to mark the first stage in the dissolution of the Carolingian Empire. TREATY OF MERSEN, 870 A.D. A second treaty, made at Mersen in Holland, was entered into by Louis and Charles, after the death of their brother Lothair. They divided between themselves Lothair's kingdom north of the Alps, leaving to his young son the possession of Italy and the empty title of "emperor." The Treaty of Mersen may be said to mark the second stage in the dissolution of the Carolingian Empire. That empire, as such, had now ceased to exist. [Illustration: Map, THE FRANKISH DOMINIONS AS DIVIDED BY THE TREATIES OF VERDUN (843 A.D.) AND MERSEN (870 A.D.)] IMPORTANCE OF THE TWO TREATIES The territorial arrangements made by the treaties of Verdun and Mersen foreshadowed the future map of western Europe. The East Frankish kingdom of Louis, inhabited almost entirely by Germanic peoples, was to develop into modern Germany. The West Frankish kingdom of Charles, inhabited mainly by descendants of Romanized Gauls, was to become modern France. Lothair's kingdom, separated into two parts by the Alps, never became a national state. Italy, indeed, might be united under one government, but the long, narrow strip north of the Alps had no unity of race, no common language, and no national boundaries. It was fated to be broken into fragments and to be fought over for centuries by its stronger neighbors. Part of this territory now forms the small countries of Belgium, Holland, and Switzerland, and another part, known as Alsace and Lorraine, [17] still remains a bone of contention between France and Germany. RENEWED BARBARIAN INVASIONS