In the aftermath of the First World War, the Fiume Question ("La Questione di Fiume" in Italian, "Riječko Pitanje" in Croatian), part of the larger Adriatic Question or Adriatic Problem concerned the fate of the territory that was part of the Corpus Separatum of Fiume, the and one of the only two free ports of the Austro-Hungarian empire.The roots of the problem lay in the ethnically mixed population of the Corpus Separatum in a time of growing nationalism, Italian irredentism and Yugoslavism, which led ultimately to the creation of the State of Slovenes, Croats and Serbs. The question was a major barrier to agreement at the 1919 Paris Peace Conference but was partially resolved by the Treaty of Rapallo between Italy and Yugoslavia on 12 November 1920.