Charles V. had ordered in his will that the right of his successors to the crown of Navarre should be examined, and that it should be restored to its rightful owners if it had been unjustly seized. In 1561, Philip II., who had not yet thought of executing the intentions of his father, perceiving that the king, Anthony de Bourbon, inclined towards Calvinism, entered into a negociation with him on this subject. In order to attach him to the Catholic party, Philip promised to obtain a dissolution of his marriage with Jane, who was a heretic, to induce his holiness to excommunicate her, and to give her states to him, with the consent of the Kings of France and Spain; to restore Navarre, or to give the island of Sardinia in exchange for it, and to negotiate a marriage between him and Mary Stuart, Queen of Scotland. Anthony accepted this offer, but died before it could be executed. Philip then, through the intrigues of his agents at Rome, obtained the excommunication of Jane d'Albret, and that her states should be offered to the first Catholic prince who would take possession of them on the condition of expelling the heretics. Pius V. published a bull on the 28th September, 1563, excommunicating Queen Jane, for having adopted the heresy of Calvin, and promulgating his doctrines in her states; and according to the requisition of the procurator-fiscal of the Inquisition, his Holiness summoned her to appear at Rome, within six months, to answer these charges. Catherine de Medicis, regent of France, who was then reconciled to the Prince of Condé, the brother of the late King of Navarre, was displeased at the Inquisition of Rome; and in order to stop the proceedings, sent an ambassador extraordinary to the Pope, with a very learned memorial, which has been printed, with the bull, in the _Mémoires du Prince de Condé_. Charles IX., and Catherine de Medicis, his mother, wrote to Philip II., (who was married to Elizabeth of France, the daughter of Catherine,) and informed him of what had passed, requesting that he would act in concert with them. Philip replied, that he not only disapproved of the conduct of the court of Rome, but he offered to protect the Princess Jane against any one who should attempt to deprive her of her states. It has, however, been proved by the letters of the French king to the Cardinal d'Armagnac, that Philip at the same time offered assistance to the Catholic subjects of Jane, to induce them to rebel against her, and that he privately introduced Spanish troops into her territories. This event was the origin of a confederation, known by the name of the _Catholic League_, which forms part of the histories of M. de Varillas, and of the secret memoirs of M. de Villeroi.