The Battle of Nicopolis took place on 25 September 1396 and resulted in the rout of an allied crusader army of Hungarian, Croatian, Bulgarian, Wallachian, French, Burgundian, German, and assorted troops (assisted by the Venetian navy) at the hands of an Ottoman force, raising the siege of the Danubian fortress of Nicopolis and leading to the end of the Second Bulgarian Empire. It is often referred to as the Crusade of Nicopolis as it was one of the last large-scale Crusades of the Middle Ages, together with the Crusade of Varna in 1443–1444.

Battle of Nicopolis - Wikipedia