From the end of the ninth to the end of the tenth century, two families were, in French history, the representatives and instruments of the two systems thus confronted and conflicting at that epoch, the imperial which was falling, and the feudal which was rising. After the death of Charlemagne, his descendants, to the number of ten, from Louis the Debonnair to Louis the Sluggard, strove obstinately, but in vain, to maintain the unity of the empire and the unity of the central power. In four generations, on the other hand, the descendants of Robert the Strong climbed to the head of feudal France. The former, though German in race, were imbued with the maxims, the traditions, and the pretensions of that Roman world which had been for a while resuscitated by their glorious ancestor; and they claimed it as their heritage. The latter preserved, at their settlement upon Gallo-Roman territory, Germanic sentiments, manners, and instincts, and were occupied only with the idea of getting more and more settled, and greater and greater in the new society which was little by little being formed upon the soil won by the barbarians, their forefathers. Louis the Ultra-marine and Lothaire were not, we may suppose, less personally brave than Robert the Strong and his son Eudes; but when the Northmen put the Frankish dominions in peril, it was not to the descendants of Charlemagne, not to the emperor Charles the Fat, but to the local and feudal chieftain, to Eudes, count of Paris, that the population turned for salvation: and Eudes it was who saved them.