The strength that Charlemagne had instilled in the nation subsisted enough under Louis the Debonaire so that the state could sustain its grandeur and be respected by foreigners. The prince’s mind was weak, but the nation was on a war footing. Authority was waning within, yet might did not seem to be diminishing without.
Charlemagne, his father, and his grandfather governed the monarchy in succession. The first flattered the avarice of men of war ; the two others that of the clergy ; the children of Louis the Debonaire provoked the ambition of both.
In the French constitution, the king, the nobility, and the clergy had in their hands all the authority of the state. Charles Martel, Pépin, and Charlemagne sometimes made alliances with one of the two parties to contain the other, and almost always with both of them ; but the children of Louis the Debonaire detached both of these bodies from the king,  and royal authority revealed itself too weak.