The imperial policy of Charles the Great constitutes a preface to the history of the later Middle Ages. He holds the balance between nascent forces which are to distract the future by their conflicts. He pays impartial homage to ideas which statesmen less imperious or more critical will afterwards regard as irreconcilable. He is at one and the same time an autocrat, the head of a ruling aristocracy, and a popular ruler who solicits the co-operation of primary assemblies. From the highest to the lowest his subjects must acknowledge their unconditional and immediate allegiance to his person; yet he tolerates the existence of tribal duchies, he revives the Lombard kingdom, and creates that of Aquitaine, as appanages for his younger sons. He fosters the growth of territorial feudalism, and lends the sanction of royal authority to the claims of the lord upon his vassal; but simultaneously he contrives expedients for controlling feudalism and stifling its natural development. He exalts the Church, and he enslaves her. He is there to do the will of God as expounded by the clergy; but he disposes of sees and abbacies like vacant fiefs, he dictates to the Pope, he interferes with the liturgy, he claims a voice in the definition of dogma and the wording of the creed. Finally, and most striking, there is the antithesis between the two aspects of his power, the monarchical and the imperial. The Franks left to Europe the legacy of two political conceptions. They perfected the system of barbarian royalty; they outlined the ideal of a power which should transcend royalty and embrace in one commonwealth all the Catholic kingdoms of the West. On the one hand they supplied a model to be imitated by an Egbert, a Henry the Fowler, a Hugh Capet. On the other hand they inspired the wider aims of the Ottos and the Hohenstauffen. It is therefore worth our while to understand what a Carolingian king was, and what a Carolingian Emperor hoped to be.