Which 1396 battle saw an Ottoman army defeat a large European Crusader force near the Danube?

The 1396 Battle of Nicopolis saw an Ottoman army defeat a large European Crusader force near the Danube.

The battle was fought on 25 September 1396 near Nicopolis, a fortress on the Danube in what is now Bulgaria. The Crusader army included French, Burgundian, German, Hungarian, Wallachian, and other contingents. King Sigismund of Hungary was among its principal leaders, while Sultan Bayezid I commanded the Ottoman army.

The French knights launched an aggressive attack before the wider coalition had coordinated its plans. After initial success, they encountered successive Ottoman defensive positions and were surrounded. The defeat strengthened Ottoman control in the Balkans and demonstrated the danger of poorly coordinated crusading armies.

Nicopolis is sometimes confused with Varna, another major Christian-Ottoman battle fought in 1444. The two battles were separated by almost half a century.