Anti-Fascist Council for the National Liberation of Yugoslavia in the context of "Bihać"

The Socialist Federal Republic of Yugoslavia (commonly abbreviated as SFRY or SFR Yugoslavia), known from 1945 to 1963 as the Federal People's Republic of Yugoslavia, commonly referred to as Socialist Yugoslavia or simply Yugoslavia, was a country in Central and Southeast Europe. It was established in 1945, following World War II, and lasted until 1992, dissolving amid the onset of the Yugoslav Wars. Spanning an area of 255,804 square kilometres (98,766 sq mi) in the Balkans, Yugoslavia was bordered by the Adriatic Sea and Italy to the west, Austria and Hungary to the north, Bulgaria and Romania to the east, and Albania and Greece to the south. It was a one-party socialist state and federation governed by the League of Communists of Yugoslavia, and had six constituent republics: Bosnia and Herzegovina, Croatia, Macedonia, Montenegro, Serbia, and Slovenia. Within Serbia was the Yugoslav capital city of Belgrade as well as two autonomous Yugoslav provinces: Kosovo and Vojvodina.

The country emerged as Democratic Federal Yugoslavia on 29 November 1943, during the second session of the Anti-Fascist Council for the National Liberation of Yugoslavia midst World War II in Yugoslavia. Recognised by the Allies of World War II at the Tehran Conference as the legal successor state to Kingdom of Yugoslavia, it was a provisionally governed state formed to unite the Yugoslav resistance movement. Following the country's liberation, King Peter II was deposed, the monarchical rule was ended, and on 29 November 1945, the Federal People's Republic of Yugoslavia was proclaimed. Led by Josip Broz Tito, the new communist government sided with the Eastern Bloc at the beginning of the Cold War but pursued a policy of neutrality following the 1948 Tito–Stalin split; it became a founding member of the Non-Aligned Movement, and transitioned from a command economy to market-based socialism. The country was renamed Socialist Federal Republic of Yugoslavia in 1963.

Democratic Federal Yugoslavia, also known as Democratic Federative Yugoslavia (DF Yugoslavia or DFY), was a provisional state established during World War II on 29 November 1943 through the Second Session of the Anti-Fascist Council for the National Liberation of Yugoslavia (AVNOJ). The National Committee for the Liberation of Yugoslavia (NKOJ) was its original executive body. Throughout its existence it was governed by Marshal Josip Broz Tito as prime minister.

It was recognized by the Allies at the Tehran Conference, along with the AVNOJ as its deliberative body. The Yugoslav government-in-exile of King Peter II in London, partly due to pressure from the United Kingdom, recognized the AVNOJ government with the Treaty of Vis, signed on 16 June 1944 between the prime minister of the government-in-exile, Ivan Šubašić, and Tito. With the Treaty of Vis, the government-in-exile and the NKOJ agreed to merge into a provisional government as soon as possible. The form of the new government was agreed upon in a second Tito–Šubašić agreement signed on 1 November 1944 in the recently liberated Yugoslav capital of Belgrade. This Yugoslavia became one of the founding members of the United Nations upon the signing of the UN Charter in October 1945.

The Ustaše (pronounced [ûstaʃe]), also known by anglicised versions Ustasha or Ustashe, was a Croatian fascist and ultranationalist organization active, as one organization, between 1929 and 1945, formally known as the Ustaša – Croatian Revolutionary Movement (Croatian: Ustaša – Hrvatski revolucionarni pokret). From its inception and before the Second World War, the organization engaged in a series of terrorist activities against the Kingdom of Yugoslavia, including collaborating with IMRO to assassinate King Alexander I of Yugoslavia in 1934. During World War II in Yugoslavia, the Ustaše went on to perpetrate the Holocaust and genocide against its Jewish, Serb and Roma populations, killing hundreds of thousands of Serbs, Jews, Roma, as well as Muslim and Croat political dissidents.

The ideology of the movement was a blend of fascism, Roman Catholicism and Croatian ultranationalism. The Ustaše supported the creation of a Greater Croatia that would span the Drina River and extend to the border of Belgrade. The movement advocated a racially "pure" Croatia and promoted genocide against Serbs—due to the Ustaše's anti-Serb sentiment—and Holocaust against Jews and Roma via Nazi racial theory, and persecution of anti-fascist or dissident Croats and Bosniaks. The Ustaše viewed the Bosniaks as "Muslim Croats", and as a result, Bosniaks were not persecuted on the basis of race. The Ustaše espoused Roman Catholicism and Islam as the religions of the Croats and condemned Orthodox Christianity, which was the main religion of the Serbs. Roman Catholicism was identified with Croatian nationalism, while Islam, which had a large following in Bosnia and Herzegovina, was praised by the Ustaše as the religion that "keeps true the blood of Croats."