The Congress of Berlin (13 June – 13 July 1878) was a meeting of the leading statesmen of Europe's Great Powers and the Ottoman Empire. In the wake of the Russo-Turkish War (1877–1878) that ended with a decisive victory for Russia and her Orthodox Christian allies (subjects of the Ottoman Empire before the war) in the Balkan Peninsula, the urgent need was to stabilise and reorganise the Balkans, and set up new nations. German Chancellor Otto von Bismarck, who led the Congress, undertook to adjust boundaries to minimise the risks of major war, while recognising the reduced power of the Ottomans, and balance the distinct interests of the great powers.