Leo formally excommunicated Luther by bull of Jan. 3, 1521; and in a brief directed the emperor to take energetic measures against heresy. On May 21, 1521, Henry VIII of England sent to Leo his book against Luther on the seven sacraments. The pope in return conferred on the king of England the title "De fender of the Faith" by bull of Oct. II, 1521 Neither the imperial edict nor the work of Henry VIII. stayed the Lutheran move ment. It was under Leo X. also that the Protestant movement had its beginning in Scandinavia. The pope had repeatedly used the rich northern benefices to reward members of the Roman curia, and in 1516 he sent the grasping and impolitic Arcimboldi as papal nuncio to Denmark to collect money for St. Peter's. King Christian II. expelled the nuncio and summoned (152o) Lutheran theologians to Copenhagen, and proceeded to abolish the jurisdiction of Rome in Denmark. Leo sent a new nuncio to Copenhagen (1521) in the person of the Minorite Francesco de Potentia, who readily absolved the king and received the rich bishopric of Skara. Neither the pope nor his legate, however, took any steps to remove abuses or otherwise reform the Scandinavian churches.
That Leo did not do more to check the tendency toward heresy and schism in Northern Europe is partly explained by political complications, and by his own preoccupation with schemes of papal and Medicean aggrandizement in Italy. The death of the emperor Maximilian on Jan. 12, 1519, had seriously affected the situation. Leo allowed it to appear at first that he favoured Francis I. while really working for the election of some minor German prince. He finally accepted Charles I. of Spain as inevitable, and the election of Charles (June 28, 1519) revealed Leo's desertion of his French alliance, a step facilitated by the death of Lorenzo de' Medici and his French wife. Leo desired to unite Ferrara, Parma and Piacenza to the States of the Church. An attempt in 1519 to seize Ferrara failed, and in May 1521 a treaty of alliance was signed at Rome between pope and emperor. Milan and Genoa were to be taken from France and restored to the Empire, and Parma and Piacenza were to be given to the Church on the expul sion of the French. The expense of enlisting Io,000 Swiss was to be borne equally by pope and emperor. Charles took Florence and the Medici family under his protection and promised to punish all enemies of the Catholic faith. Leo agreed to invest Charles with Naples, to crown him emperor, and to aid in a war against Venice. Henry VIII. announcd his adherence to the League in August.
Francis I. had already begun war with Charles in Navarre, and in Italy, too, the French made the first hostile movement (June 23, 1521). Leo lived to hear of the capture of Milan from the French and of the occupation by papal troops of the long-coveted prov inces (November 1521). He died suddenly on Dec. 1, 1521. His successor was Adrian VI.
Leo was friendly with King Emmanuel of Portugal on account of the latter's missionary enterprises in Asia and Africa. His con cordat with Florence (1516) guaranteed the free election of the clergy in that city. His constitution of March 1, 1519 condemned the king of Spain's claim to refuse the publication of papal bulls. He maintained close relations with Poland because of the Turkish advance and the Polish contest with the Teutonic Knights. His bull of July I, 1519, which regulated the discipline of the Polish Church, was later transformed into a concordat by Clement VII. Leo showed special favours to the Jews and permitted them to erect a Hebrew printing-press at Rome. He approved the forma tion of the Oratory of Divine Love, a group of pious men at Rome which later became the Theatine Order, and he canonized Francesco di Paola.
Leo X. was a patron of learning, and made Rome the centre of European culture. While yet a cardinal, he had restored the church of Sta. Maria in Dominica after Raphael's designs; and as pope he built S. Giovanni on the Via Giulia after designs by Jacopo Sansovino and pressed forward the work on St. Peter's and the Vatican under Raphael and Chigi. His constitution of Nov. 5, 1513 reformed the Roman university, which had been neglected by Julius II. ; although it never attained to the impor tance of Padua or Bologna, it nevertheless possessed in 1514 an excellent faculty of eighty-eight professors. Leo called Theodore Lascaris to Rome to give instruction in Greek, and established a Greek printing-press from which the first Greek book printed at Rome appeared in 1515. He made Raphael custodian of the classical antiquities of Rome and the vicinity. The distinguished Latinists Pietro Bembo (1470--1547) and Jacopo Sadoleto were papal secretaries, as well as the famous poet Bernardo Accolti (d. 1534). Poets and literati were bishops, or papal scrip tors or abbreviators, or in other papal employ. Leo's lavish expenditure exhausted within two years the hard savings of Julius II. To fill the treasury he created new offices and sold them. He sold cardinals' hats. He sold membership in the "Knights of Peter." He borrowed large sums from bankers, curials, princes and Jews.