On the eastern shore of the Baltic, also, the march of German civilization received an almost fatal check. The two strongest neighbors of the German Order, the Poles and Lithuanians, were now united under one crown, and they defeated the army of the Order, 60,000 strong, under the walls of Wilna, in 1389. After an unsatisfactory peace of some years, hostilities were again resumed, and both sides prepared for a desperate and final struggle. Each raised an army of more than 100,000 men, among whom, on the Polish side, there were 40,000 Russians and Tartars. The decisive battle was fought at Tannenberg, in July, 1410, and the German Order, after losing 40,000 men, retreated from the field. It was compelled to give up a portion of its territory to Poland, and pay a heavy tribute: from that day its power was broken, and the Slavonic races encroached more and more upon the Germans along the Baltic. [Sidenote: 1410. THE ANTI-EMPEROR RUPERT.] During this same period Holland was rapidly becoming estranged from the German Empire, and France had obtained possession of the greater part of Flanders. Luxemburg and part of Lorraine were incorporated with Burgundy, which was rising in power and importance, and had become practically independent of Germany. There was now no one to guard the ancient boundaries, and probably nothing but the war between England and France prevented the latter kingdom from greatly increasing her territory at the expense of the Empire. Although Rupert of the Palatinate acquired but a limited authority in Southern Germany, he is generally classed among the German Emperors, perhaps because Wenzel's power, after the year 1400, was no greater than his own. The confusion and uncertainty in regard to the Imperial dignity lasted until 1410, when Rupert determined to make war upon the Archbishop of Mayence--who had procured his election, and since the League of Marbach was his chief enemy--as the first step towards establishing his authority. In the midst of his preparations he died, on the 18th of May, 1410. CHAPTER XXII. THE REIGN OF SIGISMUND AND THE HUSSITE WAR. (1410--1437.)