The controlling spirit of the thirteenth century was Innocent III. "Since Gregory the Seventh's time the pope had claimed the empire of the world, and taken upon himself the responsibility of its future state. Raised to a towering height, he but saw the more clearly the perils by which he was environed. He occupied the spire of the prodigious edifice of Christianity in the middle age, that cathedral of human kind, and sat soaring in the clouds on the apex of the cross, as when from the spire of Strasburg the view takes in forty towns and villages on the banks of the Rhine." From this eminence Pope Innocent surveyed the politics of Europe, and put forth his mandates to bring the power and wealth of the nations into the treasury of the church. No measures had ever been adopted which combined so effectually to move the passions of an ardent age, in a direction indicated by papal authority, as the expeditions to the Holy Land. Louis and Philip of France and Henry of England had taxed their subjects for the benefit of the crusade. Pope Innocent went a step farther, and gave a new character to the sacred wars by imposing a similar tax upon the clergy. The eloquent pontiff described the ruin of Jerusalem, the triumphs of the Moslems, and the disgrace of Christendom; and, like his predecessors, promised redemption from sins and plenary indulgence to all who should serve in Palestine. An ignorant priest, Fulk of Neuilly, took up the word of exhortation, and with less piety than Peter the Hermit and greater zeal than St. Bernard, itinerated through the cities and villages of France, publishing the command of the successor of St. Peter. The situation of the principal monarchs was unfavorable to the pious undertaking. The sovereignty of Germany was disputed by the rival houses of Brunswick and Suabia, the memorable factions of the Guelphs and Ghibelines. Philip Augustus was engaged in projects to wrest from the King of England his transmarine dominions, and John was incapable of any project beyond the narrow circle of his personal pleasures and preferences.