scene of Mohäcs to the Sultan. Unresisted, the Turkish forces swept over the plains of Hungary, crossed the imperial frontier, and on September 20 planted their standards before the walls of Vienna. But over these the Crescent was never destined to wave, and the brilliant defence of Vienna in 1529 stopped the first, as a still more famous defence a hundred and fifty years later foiled the last, Turkish onslaught on Germany. The valour of the citizens, the excellence of the artillery, with which the late Emperor Maximilian had furnished the city, and the early rigour of winter supplied the defects of the Habsburg power, and on October 15 Solyman raised the siege. Ferdinand failed to make adequate use of the Sultan's retreat; lack of pay caused a mutiny of landsknechte; and though Gran fell into his hands he could not recapture Buda, and the greater part of Hungary remained under the nominal rule of Zapolya, but real control of the Turk.
The relief of Vienna was received with mingled feelings in Germany. Luther, who had once denied the duty of Christians to fight the infidel as involving resistance to God's ordinance, had been induced to recant by the imminence of danger and the pressure of popular feeling. In 1529 he exhorted his countrymen to withstand the Turk in language as vigorous as that in which he had urged them to crush the peasants; and the retreat of the Ottoman was generally hailed as a national deliverance. But the joy was not universal, even in Germany. Secular and religious foes of the Habsburgs had offered their aid to Zapolya; while Philip of Hesse lamented the Turkish failure and hoped for another attack. The Turk was in fact the ally of the Reformation, which might have been crushed without his assistance; and to a clear-sighted statesman like Philip no other issue than ruin seemed possible from the mutual enmity of the two Protestant Churches.
The abortive result of the meeting at Rodach in June and the abandonment of the adjourned congress at Schwabach in August only stirred the Landgrave to fresh efforts in the cause of Protestant union. On the last day in September he assembled the leading divines of the two communions at his castle of Marburg with a view to smoothing over the religious dissensions which had proved fatal to their political cooperation. The conference was not likely to fail for want of eminent disputants. The two heresiarchs themselves, Luther and Zwingli, were present, and their two chief supporters, Melanchthon and Oecolampadius. The Zwinglian cities of Germany were represented by Bucer and Hedio of Strassburg; the Lutherans by Justus Jonas and Caspar Cruciger from Wittenberg, Myconius from Gotha, Brenz from Hall, Osiander from Nürnberg, and Stephen Agricola from Augsburg. But they came in different frames of mind; Luther prophesied failure from the first, and it was with the greatest difficulty that Melanchthon could be induced even to discuss accommodation with such impious doctrines as Zwingli's. On the other hand the Zurich Reformer started with
