With the consent of the pope he summoned a general council to meet at Trent on the confines of his own Austrian territories, where he could easily have every thing under his own control. He did every thing in his power, in the meantime to promote division among the Protestants, by trying to enter into private negotiations with the Protestant princes. He had the effrontery to urge the Protestants to send their divines to the council of Trent, and agreed to abide by its decisions, even when that council was summoned by the pope, and was to be so organized as to secure an overwhelming majority to the papists. The Protestants, of course, rejected so silly a proposition, and refused to recognize the decrees of such a council as of any binding authority.
In preparation for enforcing the decrees which he intended to have enacted by the council of Trent, Charles obtained from the pope thirteen thousand troops, and five hundred thousand ducats (one million one hundred thousand dollars). He raised one army in the Low Countries to march upon Germany. He gathered another army in his hereditary States of Austria. His brother Ferdinand, as King of Hungary and Bohemia, raised a large army in each of those dominions. The King of France mustered his legions, and boasted of the condign punishment to which he would consign the heretics. The pope issued a decree offering the entire pardon of all sins to those who should engage in this holy war for the extirpation of the doctrines of the reformers.
The Protestants were for a moment in consternation in view of the gatherings of so portentous a storm. The emperor, by false professions and affected clemency, had so deceived them that they were quite unprepared for so formidable an attack. They soon, however, saw that their only salvation depended upon a vigorous defense, and they marshaled their forces for war. With promptness and energy which even astonished themselves, they speedily raised an army which, on the junction of its several corps, amounted to eighty thousand men. In its intelligence, valor, discipline and equipments, it was probably the best army which had ever been assembled in the States of Germany. Resolutely they marched under Schartlin, one of the most experienced generals of the age, toward Ratisbon, where the emperor was holding a diet.