It was the Prince’s shoulder upon which the Emperor leaned at the abdication; the Prince’s hand which bore the imperial insignia of the discrowned monarch to Ferdinand, at Augsburg. With these duties his relations with Charles were ended, and those with Philip begun. He was with the army during the hostilities which were soon after resumed in Picardy; he was the secret negotiator of the preliminary arrangement with France, soon afterwards confirmed by the triumphant treaty of April, 1559. He had conducted these initiatory conferences with the Constable Montmorency and Marshal de Saint Andre with great sagacity, although hardly a man in years, and by so doing he had laid Philip under deep obligations. The King was so inexpressibly anxious for peace that he would have been capable of conducting a treaty upon almost any terms. He assured the Prince that “the greatest service he could render him in this world was to make peace, and that he desired to have it at any price what ever, so eager was he to return to Spain.” To the envoy Suriano, Philip had held the same language. “Oh, Ambassador,” said he, “I wish peace on any terms, and if the King of France had not sued for it, I would have begged for it myself.”
With such impatience on the part of the sovereign, it certainly manifested diplomatic abilities of a high character in the Prince, that the treaty negotiated by him amounted to a capitulation by France. He was one of the hostages selected by Henry for the due execution of the treaty, and while in France made that remarkable discovery which was to color his life. While hunting with the King in the forest of Vincennes, the Prince and Henry found themselves alone together, and separated from the rest of the company. The French monarch’s mind was full of the great scheme which had just secretly been formed by Philip and himself, to extirpate Protestantism by a general extirpation of Protestants. Philip had been most anxious to conclude the public treaty with France, that he might be the sooner able to negotiate that secret convention by which he and his Most Christian Majesty were solemnly to bind themselves to massacre all the converts to the new religion in France and the Netherlands. This conspiracy of the two Kings against their subjects was the matter nearest the hearts of both. The Duke of Alva, a fellow hostage with William of Orange, was the plenipotentiary