Elated by the brilliant prospect which thus opened upon him, Biron gradually became less energetic in the service of his legitimate master; and after the peace of Vervins, finding his influence necessarily diminished, he began to murmur, affecting to believe that the services which he had rendered to the sovereign had not been duly recognized; and it was at this period, according to his betrayer, that their acquaintance had commenced, an acquaintance which so rapidly ripened into friendship that ere long he became the depository of his patron's most cherished secrets. After many and anxious consultations, principally caused by the uncertainty of the Duke as to the nature of the honours which were to be conferred upon him, it had been at length resolved between the two conspirators that they should despatch a priest to the Duke of Savoy, a monk of Cîteaux to Milan, and Picoté himself to Spain, to treat with the several Princes in the name of the Maréchal; and what was even more essential to the monarch to ascertain, was the fact that a short time subsequently, and before he visited Paris, the Duke of Savoy had entered into a secret negotiation with Biron, and even led him to believe that he would bestow upon him the hand of one of his daughters, by which marriage the Maréchal would have become the cousin of the Emperor of Germany, and the nephew of the King of Spain, an alliance which, to so ambitious a spirit, opened up an opportunity of self-aggrandizement never to be realized in his own country and under his own sovereign. In return for this concession, Biron had pledged himself to his wily ally that he would provide so much occupation for Henry in the interior of his kingdom, that he should have no leisure to attempt the invasion of the marquisate of Saluzzo, a pledge which more than any other gratified M. de Savoie, who lived in constant dread of being driven from his territories. During the war the Maréchal nevertheless took several of the Duke's fortresses in Brescia; but a perfect understanding had been established between them which rendered this circumstance comparatively unimportant; and on the refusal of Henry to permit the appointment of a governor of his own selection for the citadel of Bourg, Biron became so incensed by what he designated as the ingratitude of his sovereign--though he was fully aware that by countenancing such an arrangement the King must necessarily leave the fortress entirely in his power--that he no longer restrained himself, but declared that the death of the French sovereign was essential to the accomplishment of his projects; and meanwhile he gave the Duke of Savoy, whom he thenceforward regarded as his firmest friend, constant information of the state and movements of the hostile army.