The Long Campaign (Hungarian: Hosszú hadjárat; Serbian: Дуга војна) or Balkan Campaign (hu. balkáni hadjárat) was a military campaign led by John Hunyadi and young king Władysław III of Poland (Ulaszlo I of Hungary) across the Balkans against the Ottomans from July 22, 1443 to January 25, 1444.
The Christian army started at Buda including Hungarian, Polish, Czech, German infantry and cavalry, Lithuanian reinforcements, 3000 wagons. Later, 10,000 Wallachian and Serbians joined, so the whole army was 35,000 men strong.
The first battle was at Krusevac, and Ottomans were defeated by the Hungarians. Hunyadi, at the head of the vanguard, crossed the Balkans through the Gate of Trajan, captured Niš, defeated three Turkish pashas, and, after taking Sofia, united with the royal army and defeated Sultan Murad II at Snaim. The impatience of the king and the severity of the winter then compelled him to return home, but not before he had utterly broken the Sultan's power in Bosnia, Herzegovina, Serbia, Bulgaria, and Albania.