An examination of the three main struggles shows that each of these champions of Church and State hoped to realize a definite aim which he usually sought to attain in his own way. It is most interesting to follow the ebb and flow of the tide of battle. The pope was the first to throw down the gage of battle by attempting to remove the Church from politics through the suppression of simony and the marriage of the clergy. The very boldness of Gregory in daring to alter conditions which had not been disturbed for generations, and that, too, in the face of the strongest opposition, calls forth not only surprise, but admiration, which increases as we examine the forces upon which he relied to accomplish his results, namely, the canon law, the church organization and the ban of excommunication. According to some authorities, the very year which witnessed the settlement of the first great struggle (1122), marked the birth of Frederick I, the second great champion of the rights of the empire, rightly named the imperialist Hildebrand. Selecting Charlemagne as his model, he strove not only to unify his German possessions, but to re-establish the power and authority of the empire in Europe by reasserting its right to rule Rome and the Lombard cities, and by endeavoring to unite with it the Norman possessions in the south of Italy. These attempts naturally brought him into conflict with the papacy, which feared so dangerous a neighbor on its very borders. His main reliance was in the recently-revived study of the Roman law, and in a his labors he governed himself by the maxim that “all that pleases a prince has the force of law.” Innocent III, with perhaps the highest conception of his position of any individual who had thus far occupied the chair of St. Peter, dared to assert that the Lord gave that apostle the rule not only of the Universal Church, but also the rule of the whole world. That these were not mere phrases on his lips was shown by his efforts to extend his authority to the furthest bounds of Christendom. Favored somewhat by circumstances, he became for a time the arbiter of the destinies of the empire, but at no time did he have a foeman worthy of his steel within its confines. These were rather to be found in the limits of Christendom in the rising kingdoms of France and England, whose sovereigns nevertheless trembled before his threats and repented of their misdeeds. Like Gregory VII, he asked for no stronger weapons than the terrors inspired by the wrath of Mother Church. Finally there appeared in the arena the brilliant ward of this the greatest of popes, Frederick II, aptly characterized as the first of modern kings, striving for absolute mastery in Sicily and in Germany, placing his trust, as did his illustrious ancestor in the Roman law, but utilizing at the same time his knowledge of men and the rising power of the bourgeoisie. His plans, like those of Barbarossa, met with vigorous