The Emperor, however, succeeded in his negotiations with England. On the death of James V. of Scotland, in 1542, the regent, Mary of Guise, had rejected all the advances of the English King, and continued the French alliance. Henry accordingly turned again to Charles. By the treaty of February 11, 1543, Emperor and King agreed to demand that Francis should give up his alliance with the Turk, indemnify the Empire for the sums it had incurred in the Turkish war, and, as security for the debts he owed the King of England, hand over Boulogne and other towns. If Francis refused these terms, the allies engaged themselves to pursue the war till Burgundy should be restored to Charles, and England had made good her ancient claim to Normandy and Guienne, and to the crown of France. | The military events of 1543. | Diet of Spires, Feb. 1544. Charles gains assistance | of the Empire against France. | Success of the Imperialists. In May, Charles hastily left Spain, and arrived in Germany. He secured the neutrality of John Frederick of Saxony, entered the territories of the Duke of Cleves, and forced him to resign his pretensions to Gueldres (August). In September the joint attack of Barbarossa and the Count of Enghien, at the head of the French troops, on Nice, was foiled by the approach of Doria with the Spanish fleet and the army of Milan. Francis had not even the consolation of success to requite him for the odium he incurred by his alliance with the infidel. In Hungary, indeed, the advance of Solyman was unchecked, and by the end of August nearly the whole of that country had been conquered. But even this success cost Francis dear. At the Diet of Spires, held in February 1544, Charles denounced the King of France as an enemy to Christendom. He informed the Protestants of the offers which Francis had made in 1539 to assist him against them if he would cede Milan, and therewith made further concessions with regard to the religious question. He promised that a general _free_ and Christian Council should be summoned, and that, if the Pope delayed, he would next year call a Diet for the final settlement of the religious question. The Protestants expressed their horror at the unholy alliance with the Turk, and once more the Emperor secured the aid of the Empire in his struggle with the French. At the same time, Denmark abandoned the French alliance. Francis was now threatened by a serious combination. In Piedmont, indeed, the Count of Enghien won a decisive victory over the Marquis de Guasto and the army of Milan at Cerisoles (April 11). But in June, the Imperialists, after reducing Luxembourg, invaded Champagne and advanced as far as the Marne, while the English landed on the coast. Had Henry kept his engagement and co-operated with Charles in a combined attack on Paris, the capital might have fallen. Intent, however, on his own schemes, he delayed to lay siege to Boulogne, which did not surrender till September. Indignant at