After the death of Nicholas V. the Pagan side of the Humanist movement became more and more apparent. Pius II. (1458-64), who, as Aeneas Sylvius, was well known as a clever writer of the Humanist school, seems as Pope to have been decidedly suspicious of his former friends. His own private library was filled with Christian authors, and care was taken to show favour only to those classical scholars whose writings were above reproach. Yet the cares of his office and the promotion of the crusade on which he had set his heart prevented him from taking the necessary steps for the purification of his court, and, as a result, many of the members of the College of Abbreviators were allowed to remain in office though they were really Pagan at heart. Paul II. could not tolerate such a state of affairs. He promptly abolished the College of Abbreviators, suppressed the Roman Academy, and arrested its two prominent leaders, Pomponius Laetus and Platina. If Paul II. erred on the side of severity some of his successors went to the other extreme of laxity. The period of the political Popes, from Sixtus IV. to Julius II. (1471-1513), was marked by a serious decline in the religious spirit, nor can it be said that the policy of the Popes was calculated to check the downward tendency. Their attention was occupied too much by the politics of the petty Italian States to permit them to fulfil the duties of their high office; and, as a consequence, the interests of religion were neglected. Sixtus IV. adopted the friendly attitude of Nicholas V. towards the Renaissance. The College of Abbreviators was restored, the Roman Academy was recognised, and Platina was appointed librarian. The manuscripts in the Vatican Library were increased, more ample accommodation was provided, and every facility was given to scholars to consult the papal collection. Hence it is that Sixtus IV. is regarded generally as the second founder of the Vatican Library.