Battle of Nicopolis
In the latter half of the 14th century, the Ottoman Empire proceeded to advance north and west in the Balkans, completely subordinating Thrace and much of Macedonia after the Battle of Maritsa in 1371. Sofia fell in 1382, followed by the capital of the Second Bulgarian Empire Tarnovgrad in 1393, and the northwest remnants of the state after the Battle of Nicopolis in 1396.