II . 175
pire came to an end in Europe, and for sixty years a Latin Empire kept watch on the Bosphorus.
The Papal guardian of Frederic met with no success in carrying out his German policy. At first he maintained neutrality in the struggle for the throne between Philip of Swabia and Otto the Guelph, Then, because Philip in his capacity as administrator of the Mathildan do- main had interfered with the rights of the Church, and also because the entire Hohenstaufen faction did not recognize the Papal gains in the Papal States, Innocent went over to the side of Otto, who was rich in promises. He imposed the ban on Otto's opponents and in an- swer to their protest declared that, though the German princes un- questionably had the right to elect their King, it was the Pope's priv- ilege to examine the king elected before crowning him Emperor, and, in case that two candidates were chosen, to decide in favour of the one who appeared most likely to perform his royal duties. Philip gained the larger number of supporters and had already succeeded in inducing Innocent to free him from the ban, when he was murdered by a Wittelsbach assassin in 1208. Otto, who was betrothed to Phil- ip's daughter, was now unquestionably King and renewed all the golden promises he had made to the Pope. But once crowned Em- peror (1209) he was no longer anxious to keep them. What was still worse, he wrecked the political plan on which the Curia had staked its greatest hopes. It sought to prevent once and forever the union under one rule of the Neapolitan Sicilian Kingdom and the Empire, since this would have placed the Italian Church states anew under the control of the Empire. When Otto, who had already sub- jugated the mainland, wanted to conquer Sicily also, the Pope first imposed the ban on him and then induced the German princes to depose him and elect a new ruler. The choice fell on Frederic, as Henry VI had already foreseen, and Innocent approved. The reason was that Frederic recognized the Pope's right to determine the fate of Sicily, and obediently conveyed the Sicilian crown to his infant son. The Hohenstaufen monarch was then seventeen years old and was received with enthusiasm in the land of his ancestors. He became King of Germany; and by the Golden Bull of Ager he promised, with the assent of the princes, to fulfill all the spiritual and temporal requests,