One event came to embitter his last days. The Scandinavian Goths, now known as Norsemen, were beginning to build their "sea-dragons" and sally forth on voyages of plunder and conquest. They laid waste the shores of Holland and Northern France, and the legend says that Charlemagne burst into tears of rage and shame, on perceiving his inability to subdue them or prevent their incursions. One of his last acts was to order the construction of a fleet at Boulogne, but when it was ready the Norse Vikings suddenly appeared in the Mediterranean and ravaged the southern coast of France. Charlemagne began too late to make the Germans either a naval or a commercial people: his attempt to unite the Main and Danube by a canal also failed, but the very design shows his wise foresight and his energy. [Sidenote: 813.] Towards the end of the year 813, feeling his death approaching, he called an Imperial Diet together at Aix-la-Chapelle, to recognize his son Ludwig as his successor. After this was done, he conducted Ludwig to the Cathedral, made him vow to be just and God-fearing in his rule, and then bade him take the Imperial crown from the altar and set it upon his head. On the 28th of January, 814, Charlemagne died, and was buried in the Cathedral, where his ashes still repose. CHAPTER XII. THE EMPERORS OF THE CAROLINGIAN LINE. (814--911.) Character of Ludwig the Pious. --His Subjection to the Priests. --Injury to German Literature. --Division of the Empire. --Treatment of his Nephew, Bernard. --Ludwig's Remorse. --The Empress Judith and her Son. --Revolt of Ludwig's Sons. --His Abdication and Death. --Compact of Karl the Bald and Ludwig the German. --The French and German Languages. --The Low-German. --Lothar's Resistance. --The Partition of Verdun. --Germany and France separated. --The Norsemen. --Internal Troubles. --Ludwig the German's Sons. --His Death. --Division of Germany. --Karl the Fat. --His Cowardice. --The Empire restored. --Karl's Death. --Duke Arnulf made King. --He defeats the Norsemen and Bohemians. --His Favors to the Church. --The "Isidorian Decretals." --Arnulf Crowned Emperor. --His Death. --Ludwig the Child. --Invasions of the Magyars. --End of the Carolingian line in Germany. [Sidenote: 814. LUDWIG THE PIOUS.]