If the three armies of the Margrave of Baden, of Christian of Brunswick, and of Mansfeld, could be brought to co-operate, Tilly, even if supported by Cordova's Spaniards, would be in a decided numerical inferiority. But he had the advantage of a central situation, of commanding veteran troops by whom he was trusted, and above all of being able to march or remain quiet at his pleasure, as not being dependent on mere pillage for his commissariat. He was inspired, too, by a childlike faith in the cause for which he was fighting as the cause of order and religion against anarchy and vice. SECTION IV.--_The Fight for the Lower Palatinate._ [Sidenote: § 1. Frederick joins Mansfeld in the Palatinate.] By the middle of April the hostile armies were in movement, converging upon the Palatinate, where the fortresses of Heidelberg, Mannheim, and Frankenthal were safe in Vere's keeping. Frederick himself had joined Mansfeld's army in Alsace, and his first operations were attended with success. Effecting a junction with the Margrave of Baden he inflicted a severe check upon Tilly at Wiesloch. The old Walloon retreated to Wimpfen, calling Cordova to his aid, and he did not call in vain. Mansfeld, on the other hand, and the Margrave could not agree. Each had his own plan for the campaign, and neither would give way to the other. Besides, there were no means of feeding so large an army if it kept together. Mansfeld marched away, leaving the Margrave to his fate. [Sidenote: § 2. Battle of Wimpfen.] The battle of Wimpfen was the result. On May 6 Tilly and Cordova caught the Margrave alone, and defeated him completely. As soon as the action was over, Cordova left the field to resist the progress of Mansfeld; and Mansfeld, whose men were almost starving, was unable to overcome serious resistance. There was nothing for it but a speedy retreat to Alsace. [Sidenote: § 3. The Congress at Brussels.] In the meantime the diplomatists had met at Brussels. After some difficulties of form had been got over, Sir Richard Weston, the representative of England, sent to ask Frederick to agree to a truce. When the message reached him the battle of Wimpfen had not been fought, and his hopes were still high. A truce, he wrote to his father-in-law, would be his utter ruin. The country was exhausted. Unless his army lived by plunder it could not exist. A few days later he was a beaten man. On May 13 he gave way, and promised to agree to the truce. On the 28th all was again changed. He had learned that the Margrave of Baden hoped to bring back his army into the field. He knew that Christian of Brunswick was approaching from beyond the Main; and he informed Weston that he could do nothing to assist the negotiations at Brussels. [Sidenote: § 4. Seizure of the Landgrave of Darmstadt.]