Duke Bernard's successes, nevertheless, had drawn a part of the Imperialists from Northern Germany, and in 1638 Banner, having recruited his army, marched through Brandenburg and Saxony into the heart of Bohemia, burning and plundering as he went, with no less barbarity than Tilly or Wallenstein. Although repulsed in 1639, near Prague, by the Archduke Leopold (Ferdinand III.'s brother), he only retired as far as Thuringia, where he was again strengthened by Hessian and French troops. In this condition of affairs, Ferdinand III. called a Diet, which met at Ratisbon in the autumn of 1640. A majority of the Protestant members united with the Catholics in their enmity to Sweden and France, but they seemed incapable of taking any measures to put an end to the dreadful war: month after month went by and nothing was done. Then Banner conceived the bold design of capturing the Emperor and the Diet. He made a winter march, with such skill and swiftness, that he appeared before the walls of Ratisbon at the same moment with the first news of his movement. Nothing but a sudden thaw, and the breaking up of the ice in the Danube, prevented him from being successful. In May, 1641, he died, his army broke up, and the Emperor began to recover some of the lost ground. Several of the Protestant princes showed signs of submission, and ambassadors from Austria, France and Sweden met at Hamburg to decide where and how a Peace Congress might be held. [Sidenote: 1642. VICTORIES OF TORSTENSON.] In 1642 the Swedish army was reorganized under the command of Torstenson, one of the greatest of the many distinguished generals of the time. Although he was a constant sufferer from gout and had to be carried in a litter, he was no less rapid than daring and successful in all his military operations. His first campaign was through Silesia and Bohemia, almost to the gates of Vienna; then, returning through Saxony, towards the close of the year, he almost annihilated the army of Piccolomini before the walls of Leipzig. The Elector John George, fighting on the Catholic side, was forced to take refuge in Bohemia. Denmark having declared war against Sweden, Torstenson made a campaign in Holstein and Jutland in 1643, in conjunction with a Swedish fleet on the coast, and soon brought Denmark to terms. The Imperialist general, Gallas, followed him, but was easily defeated, and then Torstenson, in turn, followed him back through Bohemia into Austria. In March, 1645, the Swedish army won such a splendid victory near Tabor, that Ferdinand III. had scarcely any troops left to oppose their march. Again Torstenson appeared before Vienna, and was about commencing the siege of the city, when a pestilence broke out among his troops and compelled him to retire, as before, through Saxony. Worn out with the fatigues of his marches, he died before the end of the year, and the command was given to General Wrangel.