Fortunately for the interests of Rudolph and the peace of Germany, Gregory X was prudent, humane, and generous, and from a long experience of worldly affairs had acquired a profound knowledge of men and manners.  An ardent zeal for the propagation of the Christian faith was the leading feature of his character, and the object of his greatest ambition was to lead an army of crusaders against the infidels.  To the accomplishment of this purpose he directed his aims, and, like a true father of Christendom, was anxious to appease instead of fomenting the troubles of Europe, and to consolidate the union of the German states, which it had been the policy of his predecessors to divide and disunite.  By the most insinuating address he knew how to conciliate the affections of those who approached him, and to bend to his purpose the most steady opposition; and he endeavored to gain by extreme affability and the mildness of his deportment what his predecessors had extorted by the most extravagant pretensions.

The ambassadors of Rudolph were received with complacency by the Pope, and obtained his sanction by agreeing, in the name of their master, to the same conditions which Otho IV and Frederick II had sworn to observe; by confirming all the donations of the emperors, his predecessors, to the papal see; by promising to accept no office or dignity in any of the papal territories, particularly in the city of Rome, without the consent of the Pope; by agreeing not to disturb nor permit the house of Anjou to be disturbed in the possession of Naples and Sicily, which they held as fiefs from the Roman see; and by engaging to undertake in person a crusade against the infidels.  In consequence of these concessions, Gregory gave the new King of the Romans his most cordial support, refused to listen to the overtures of Ottocar, and after much difficulty finally succeeded in persuading Alfonso to renounce his pretensions to the imperial dignity.

An interview in October, 1275, between Rudolph and Gregory at Lausanne, concluded his negotiations with the Roman see, and gave rise to a personal friendship between the heads of the Church and the empire, who were equally distinguished for their frank and amiable qualities.  In this interview Rudolph publicly ratified the articles which his ambassadors had concluded in his name; the electors and princes who were present followed his example, and Gregory again confirmed the election of Rudolph, on condition that he should repair to Rome the following year to receive the imperial crown.  At the conclusion of this ceremony the new Emperor, with his consort and the princes of the empire, assumed the cross, and engaged to undertake a crusade against the infidels.