Franciscan "Jew-baiter" arranged a forced disputation at Rome with a certain Gamaliel called "Synagogæ Romanæ magister". Between 1451 and 1453, his fiery sermons against Jews persuaded many southern German regions to expel their entire Jewish population, and in Silesia, then Kingdom of Bohemia, at Wroclaw many were burned at the stake. The soldier saint After the Fall of Constantinople in 1453, the Ottoman Empire, under Sultan Mehmed II, threatened Christian Europe. That following year Pope Callixtus III sent John, who was already aged seventy, to preach a Crusade against the invading Turks at the Imperial Diet of Frankfurt. Gaining little response in Bavaria and Austria, he decided to concentrate his efforts in Hungary. By July 1456 Capistrano managed to raise a large, albeit poorly trained force made up of peasants and local countryside landlords, with which he advanced towards Belgrade which was under siege by Turkish forces.. Though poorly equipped they were highly motivated. Capistrano and John Hunyadi traveled together, though commanding the army separately. Between them, they had gathered around 40,000–50,000 troops altogether. Hunyadi managed to break the naval blockade on the Danube, and breach the siege, bringing reinforcements and supplies to the city. By some accounts, the peasant soldiers started a spontaneous action, and forced Capistrano and Hunyadi to take advantage of it. Despite Hunyadi's orders to the defenders not to try to loot the Ottoman positions, some of the units crept out from demolished ramparts, took up positions across from the Ottoman line, and began harassing enemy soldiers. Ottoman Sipahis tried without success to disperse the harassing force. As more defenders joined those outside the wall. What began as an isolated incident quickly escalated into a full-scale battle. John of Capistrano at first tried to order his men back inside the walls, but soon found himself surrounded by about 2,000 peasant levymen. He then began leading them toward the Ottoman rear across the Sava river. At the same time, Hunyadi started a desperate charge out of the fort to take the cannon positions in the Ottoman encampment. In the aftermath of a fierce battle, the Ottomans withdrew and retreated under cover of darkness; the siege was lifted. His involvement led to Capistrano being called “the Soldier Priest”. Although he survived the battle, John fell victim to the bubonic plague, which flourished in the unsanitary conditions prevailing among armies of the day. He died on 23 October 1456