In 1410 the Teutonic order received a most crushing defeat at Tannenberg from the King of Poland, assisted by bodies of Russians, Lithuanians, and Tartars. The grand master, Ulric de Jungingen, was slain, with several hundred knights and many thousand soldiers. There is said to have been a chapel built at Gruenwald, in which an inscription declared that sixty thousand Poles and forty thousand of the army of the knights were left dead upon the field of battle. The banner of the order, its treasury, and a multitude of prisoners fell into the hands of the enemy, who shortly afterward marched against Marienberg and closely besieged it. Several of the feudatories of the knights sent in their submission to the King of Poland, who began at once to dismember the dominions of the order and to assign portions to his followers. But this proved to be premature. The knights found in Henry de Planau a valiant leader, who defended the city with such courage and obstinacy that, after fifty-seven days' siege, the enemy retired, after serious loss from sorties and sickness. A series of battles followed, and finally a treaty of peace was signed, by which the order gave up some portion of its territory to Poland. But a new enemy was on its way to inflict upon the order greater and more lasting injury than that which the sword could effect. The doctrines of Wycklif had for some time been spreading throughout Europe, and had lately received a new impulse from the vigorous efforts of John Huss in Bohemia, who had eagerly embraced them, and set himself to preach them, with additions of his own. Several knights accepted the teaching of Huss, and either retired from the order or were forcibly ejected. Differences and disputes also arose within the order, which ended in the arrest and deposition of the grand master in 1413. But the new doctrines had taken deep root, and a large party within the order were more or less favorable to them, so much so that at the Council of Constance (1415) a strong party demanded the total suppression of the Teutonic order. This was overruled; but it probably induced the grand master to commence a series of persecutions against those in his dominions who followed the principles of Huss. The treaty that had followed the defeat at Tannenberg had been almost from the first disputed by both parties, and for some years appeals were made to the Pope and the Emperor on several points; but the decisions seldom gave satisfaction or commanded obedience. The general result was the loss to the order of some further portions of its dominions.