install their own government under his "great adversary", Cardinal Francesco Soderini. Soderini encouraged the plot, exhorting both Adrian and Francis I of France to strike against Giulio and invade his allies in Sicily. This did not happen. Instead of breaking with Giulio, Adrian had Cardinal Soderini imprisoned. Afterward, the principal conspirators were "declared rebels", and some were "apprehended and beheaded; by which means Giulio was again secured [as leader of Florence]." Pope Following Adrian VI's death on 14 September 1523, Cardinal Giulio overcame the opposition of the French king and finally succeeded in being elected Pope Clement VII in the next conclave (19 November 1523). Pope Clement VII brought to the papal throne a high reputation for political ability and possessed in fact all the accomplishments of a wily diplomat. But his contemporaries considered him worldly and indifferent to the perceived dangers of the Protestant Reformation. At his accession, Clement VII sent the Archbishop of Capua, Nikolaus von Schönberg, to the Kings of France, Spain, and England, in order to bring the Italian War to an end. An early report from the Protonotary Marino Ascanio Caracciolo to the Emperor records: "As the Turks threaten to conquer Christian states, it seems to him that it is his first duty as Pope to bring about a general peace of all Christian princes, and he begs him (the Emperor), as the firstborn son of the Church, to aid him in this pious work." But the pope's attempt failed. Continental and Medici politics Francis I of France's conquest of Milan in 1524, during his Italian campaign of 1524–1525, prompted the Pope to quit the Imperial–Spanish side and to ally himself with other Italian princes, including the Republic of Venice, and France in January 1525. This treaty granted the definitive acquisition of Parma and Piacenza for the Papal States, the rule of Medici over Florence and the free passage of the French troops to Naples. This policy in itself was sound and patriotic, but Clement VII's zeal soon cooled; by his want of foresight and unseasonable economy, he laid himself open to an attack from the turbulent Roman barons, which obliged him to invoke the mediation of the emperor, Charles V. One month later, Francis I was crushed and imprisoned in the Battle of Pavia, and Clement VII went deeper in his former engagements with Charles V, signing an alliance with the viceroy of Naples.