at Leipzig, but in spite of the appeals of the preacher Matthias Hoe von Hohenegg (1580–1645) he contented himself with a formal protest. Meanwhile, Gustavus Adolphus had landed in Germany, aiming to relieve Magdeburg. Gustavus attempted to conclude an alliance with John George to allow him to cross the Elbe at Wittenberg, but John George remained hesitant to join the Protestant cause and the discussions went nowhere. Hoping that an alliance would be concluded eventually, Gustavus avoided any military action. Tilly, commander of the main imperial force, was also concerned about the possibility of an alliance, no matter how unlikely it was at the time. In order to preempt any such move, he invaded Saxony and started to ravage the countryside. This had the effect of driving John George into the alliance he had hoped to preempt, which was concluded in September 1631. The Saxon troops were present at the Battle of Breitenfeld, but were routed by the Imperials under Tilly, the elector himself seeking safety in flight. Nevertheless, he soon took the offensive after Gustavus crushed the army of Tilly . Marching into Bohemia the Saxons occupied Prague, but John George soon began to negotiate for peace and consequently his soldiers offered little resistance to Wallenstein, who drove them back into Saxony. However, for the present the efforts of Gustavus Adolphus prevented the elector from deserting him, but the position was changed by the death of the king at Lützen in 1632, and the refusal of Saxony to join the Protestant league under Swedish leadership. Still letting his troops fight in a desultory fashion against the imperials, John George again negotiated for peace, and in May 1635 he concluded the important Treaty of Prague with Ferdinand II. His reward was Lusatia and certain other additions of territory; the retention by his son Augustus of the Archbishopric of Magdeburg; and some concessions with regard to the Edict of Restitution. Almost at once he declared war upon the Swedes, but in October 1636 he was beaten at Wittstock; and Saxony, ravaged impartially by both sides, was soon in a deplorable condition. At length in September 1645 the elector was compelled to agree to a truce with the Swedes, who, however, retained Leipzig; and as far as Saxony was concerned this ended the Thirty Years' War. After the Peace of Westphalia, which with regard to Saxony did little more than confirm the