Peter no equal. The contest could not have begun under men more strongly contrasted, or more determinedly oppugnant in character, than Gregory the Ninth and Frederick the Second. Gregory retained the ambition, the vigor, almost the activity of youth, with the stubborn obstinacy, and something of the irritable petulance, of old age. He was still master of all his powerful faculties; his knowledge of affairs, of mankind, of the peculiar interests of almost all the nations in Christendom, acquired by long employment in the most important negotiations both by Innocent the Third and by Honorius the Third; eloquence which his own age compared to that of Tully; profound erudition in that learning which, in the medieval churchman, commanded the highest admiration.