Louis the German was succeeded in the East-Frankish kingdom by his son, Charles the Fat. In 884, owing to the death of the sons and the grandsons of Charles the Bald, there was no one to represent his line except a child of five years. So the aristocracy of the West-Frankish kingdom invited Charles the Fat to become their king. In this way it came about that the whole empire of Charlemagne was reunited for two or three years under a single ruler.[55] [Sidenote: Charles the Fat and the Northmen.] Charles the Fat was ill and proved an incompetent emperor, entirely unequal to the serious task of governing and protecting his vast territories. His weakness was especially shown in his pusillanimous treaties with the Northmen. When Paris was making an heroic defense against them under its count, Odo, Charles, instead of marching at the head of an army to relieve it, agreed to pay the invaders seven hundred pounds of silver if they would raise the siege. They were then permitted to take up their winter quarters far inland, in Burgundy, where they proceeded to burn and pillage at will. [Sidenote: Charles the Fat deposed and succeeded by Arnulf.] This degrading agreement so disgusted the West-Frankish nobility that they were glad to join a conspiracy set on foot by Charles' nephew, the brave Arnulf of Carinthia, who had resolved to supplant his inefficient uncle. Charles was deposed and deserted by all his former supporters in 887. No one, except Napoleon, has ever again succeeded in bringing the eastern, western, and southern parts of Charlemagne's empire under his control, even for a brief period. Arnulf, although enjoying the title of emperor, could scarcely hope to be recognized as king in all parts of the Frankish empire. Even nominal unity was no longer possible. As one of the chronicles of the time puts it, "While Arnulf was frittering away his time, many little kingdoms grew up." [Sidenote: Origin of the kingdom of Burgundy, or Arles.] In the West-Frankish territory the nobility of the northern part chose Odo, the hero of the siege of Paris, as their king; but in the south another enterprising nobleman, Count Boso of Vienne, succeeded in inducing the pope to crown him king of a certain district on the Rhone which included Provence. Immediately after Boso's death a large territory about the Lake of Geneva, which he had hoped to win for himself, became a separate kingdom under its own ruler. This region and that which Boso ruled to the south were later united into the kingdom of Burgundy, or, as it is often called, Arles.