In the thirty-ninth session of the council of Constance it had been decreed, that for the suppression and prevention of heresy and schism, at the end of five years after the dissolution of the existing council, another should be summoned; a third at the expiration of seven years from the breaking up of the second; and that after these extraordinary meetings, general councils should be regularly held once in every ten years. At the expiration of the prescribed term, therefore, Martin V. according to the tenor of the first head of this decree, summoned the representatives of the different nations of Christendom to repair to Pavia. [A. D. 1423.] Nothing however having lately occurred, particularly to interest the Christian powers in the proceedings of the Roman hierarchy, the inconsiderable numbers of this assembly formed a striking contrast with the multitudes who had a few years before this time flocked on a similar occasion to the city of Constance. The plague having made its appearance in Pavia, the council was removed to Siena, where it began to be more numerously frequented. Alfonso, king of Arragon, took this opportunity of supporting, in opposition to Martin V., the pretensions of Piero da Luna, who still assumed the name of Benedict XIII. and maintained a sort of pontifical splendour in the fortress of Paniscola. Alfonso was prompted thus to trouble the peace of the church, by the resentment which he felt against Martin, in consequence of that pontiff’s refusing to acknowledge the legitimacy of his pretensions to the throne of Naples. On the death of Ladislaus, the crown of that distracted realm was inherited by his sister, Johanna II.,[142] who soon after her accession married Jacques, count of La Marche, a prince of the royal blood of France. The ambition of Jacques, who, not contented with administering the government in the name of his wife, wished to be acknowledged as sovereign paramount of the kingdom, occasioned serious disputes between him and Joanna, which terminated in his being obliged to quit the territories of Naples, and flee to France. Soon after his arrival in that country he renounced the pursuit of secular concerns, and assumed the habit of the Franciscan order. In this conjuncture, Louis III. of Anjou revived the claims of his house upon the throne of Naples, and marched into Italy, at the head of a considerable army, with the intention of prosecuting his rights by the sword.[143] Seeing the necessity of opposing against this invader an adversary of distinguished abilities, Joanna adopted as her son, Alfonso, king of Arragon, a prince of great courage and military skill, by whose active exertions, Louis of Anjou was soon driven from the Neapolitan territories. The adopted son of Joanna being unfortunately influenced by the views of her late husband, and wishing to rule by his own sole authority, that princess was justly disgusted by his ingratitude, and in the year 1423, she annulled the act