In the aftermath of the First World War, the Adriatic Question or Adriatic Problem concerned the fate of the territories along the eastern coast of the Adriatic Sea that formerly belonged to the Austro-Hungarian Empire. The roots of the dispute lay in the secret Treaty of London, signed during the war (26 April 1915), and in growing nationalism, especially Italian irredentism and Yugoslavism, which led ultimately to the creation of Yugoslavia. The question was a major barrier to agreement at the Paris Peace Conference, but was partially resolved by the Treaty of Rapallo between Italy and Yugoslavia on 12 November 1920.