Europe. The most important contingent being that of the French led by John the Fearless, son of Philip II, Duke of Burgundy. Sigismund set out with 90,000 men and a flotilla of 70 galleys. After capturing Vidin, he camped with his Hungarian armies before the fortress of Nicopolis. Sultan Bayezid I raised the siege of Constantinople and, at the head of 140,000 men, completely defeated the Christian forces in the Battle of Nicopolis fought between the 25 and 28 September 1396. Sigismund returned by sea and through the realm of Zeta, where he ordained the local Montenegrin lord Đurađ II with the islands of Hvar and Korčula for resistance against the Turks; the islands were returned to Sigismund after Đurađ's death in April 1403. The disaster at Nicopolis angered several Hungarian lords, leading to instability in the kingdom. Deprived of his authority in Hungary, Sigismund then turned his attention to securing the succession in Germany and Bohemia, and was recognized by his childless half-brother Wenceslaus IV as Vicar-General of the whole Empire. However, he was unable to support Wenceslaus when he was deposed in 1400, and Rupert of Germany, Elector Palatine, was elected German king in his stead. Return to Hungary On his return to Hungary in 1401, Sigismund was imprisoned once and deposed twice. That year, he aided an uprising against Wenceslaus IV, during the course of which the Bohemian king was taken prisoner, and Sigismund ruled Bohemia for nineteen months. He released Wenceslaus in 1403. In the meantime, a group of Hungarian noblemen swore loyalty to the last Anjou monarch, Ladislaus of Naples, putting their hands on the relic of Saint Ladislas of Hungary in Nagyvárad (today Oradea). Ladislaus was the son of the murdered Charles II of Hungary, and thus a distant relative of the long dead King Louis I of Hungary. Ladislaus captured Zara (today Zadar) in 1403, but soon stopped any military advance. This struggle in turn led to a war with the Republic of Venice, as Ladislaus had sold the Dalmatian cities to the Venetians for 100,000 ducats before leaving for his own land. In the following years Sigismund acted indirectly to thwart Ladislaus' attempts to conquer central Italy, by allying with the Italian cities resisting him and by applying diplomatic pressure on him. Due to his frequent absences attending to business in the other countries over which he ruled, he was obliged to