The Free Territory of Trieste was an international zone bordering Italy and Yugoslavia, facing the north part of the Adriatic Sea, under direct responsibility of the United Nations Security Council in the aftermath of World War II, as a result of competing Italian and Yugoslav claims that arose from the conflict. Italy fought with the Axis powers during the war, and when the Fascist regime collapsed in 1943 and Italy capitulated, the territory was occupied by German forces who created the Operational Zone of the Adriatic Littoral, the capital of which was Trieste. The Yugoslav 4th Army and the Slovenian 9th Corps entered Trieste on 1 May 1945, after a battle in the town of Opicina.