The Papacy regularly offered crusade privileges from the 1360s generating no significant military response against Muslims in the Mediterranean. The first revival of activity was a 1390 Genoese plan to seize the Tunisian port of Al-Mahdiya. Both the Roman and Avignon popes awarded indulgences and the French king's uncle, Louis II, Duke of Bourbon, was the leader. There is little evidence of cross taking, and the exercise was more of a chivalric promenade by a small force. After a disease-ridden, nine-week siege, the Tunis crusade agreed to withdraw. After their victory at the Battle of Kosovo in 1389, the Ottomans had conquered most of the Balkans and had reduced Byzantine influence to the area immediately surrounding Constantinople, which they later besieged. In 1393, the Bulgarian Tsar Ivan Shishman lost Nicopolis to the Ottomans. In 1394 Pope Boniface IX proclaimed a new Crusade against the Turks, although the Western Schism had split the papacy. Sigismund of Luxemburg, King of Hungary, led this Crusade which involved several French nobles including John the Fearless, the son of the Duke of Burgundy, who became the Crusade's military leader. Sigismund advised the Crusaders to focus on defence when they reached the Danube, but they besieged the city of Nicopolis. The Ottomans defeated them in the Battle of Nicopolis on 25September, capturing 3,000 prisoners.