On the death of Paul V. Cardinal Ludovisi ascended the papal throne under the title of Gregory XV. (1621-23). The new Pope had been educated by the Jesuits, and had risen rapidly in the service of the Church. At the time of his election he was old and infirm, but by the appointment of his nephew Ludovico to the college of cardinals he secured for himself an able and loyal assistant. To put an end to several abuses that had taken place in connexion with papal elections he published the Bull, /Decet Romanum Pontificem/ (1622), in which were laid down minute regulations about conclaves, the most important of which were that the cardinals should vote secretly, that they should vote only for one candidate, and that no elector should vote for himself.[11] In providing funds for the assistance of the Catholic missions Gregory XV. was very generous as was also his cardinal- nephew. The success of the missionaries had been so great, and the conditions of the various countries in which they laboured so different, that proper supervision of the new provinces of the Church was by no means easy. Gregory XIII. and Clement VIII. had appointed commissions to look after the spiritual wants of particular districts, but it was reserved for Gregory XV. to establish a permanent congregation, /De Propaganda Fide/ (Bull, /Inscrutabili/, 1622) to superintend the entire field of Catholic missions. He had the honour, too, of canonising St. Ignatius of Loyola, St. Francis Xavier, and St. Philip Neri, and of approving the foundation of several new religious orders. During the Thirty Years' War he afforded every possible assistance to Ferdinand II., and helped to secure the Palatinate for Maximilian of Bavaria on the expulsion of Frederick. In return for this favour Maximilian presented the Pope with a goodly portion of the library of Heidelberg. By the judicious interposition of Gregory XV. war was averted between Spain and Austria on the one side and France, Venice, and Savoy on the other regarding the possession of the Valtelline, while in England, though the Spanish Match which he favoured was broken off, he succeeded in securing some respite for the persecuted Catholics.