Tito–Stalin split in the context of "Socialist Federal Republic of Yugoslavia"

The Iron Curtain was the political and physical boundary that divided Europe from the end of World War II in 1945 until the end of the Cold War in 1991. East of the Iron Curtain were the smaller states controlled by the Soviet Union, in 1955 formally allied by the Warsaw Pact. Many nations to the west of this geopolitical divide were NATO members. Over time these economic and military alliances developed into broader, more entrenched, cultural barriers that deepened widespread distrust on both sides. Initially, the term "Iron Curtain" was a literal description of physical barriers such as razor wire, fences, walls, minefields, and watchtowers along the borders of the opposing powers. But the term eventually took on a broader, symbolic meaning perceived as a generalized "differentness" of ideology, economy, government, and way of life that emerged when the Cold War severed earlier cultural connections between European populations.

The term's origin is often attributed to the speech "Sinews of Peace" delivered by Winston Churchill on 5 March 1946 in Fulton, Missouri where he said: "an iron curtain has descended across the Continent. Behind that line lie all the capitals of the ancient states of Central and Eastern Europe." In fact, the phrase was originally used by Queen Elisabeth of Belgium, when in 1914 when she described an "Iron Curtain" descending between her people and the nation of Germany.

The Eastern Bloc, also known as the Communist Bloc (Combloc), the Socialist Bloc, the Workers Bloc, and the Soviet Bloc, was an unofficial coalition of Communist states of Central and Eastern Europe, Asia, Africa, and Latin America that were aligned with the Soviet Union and existed during the Cold War (1947–1991). These states followed the ideology of Marxism–Leninism and various types of socialism, in opposition to the capitalist Western Bloc. The Eastern Bloc was often called the "Second World", whereas the term "First World" referred to the Western Bloc and "Third World" referred to the non-aligned countries that were mainly in Africa, Asia, and Latin America but notably also included former pre-1948 Soviet ally Yugoslavia, which was located in Europe.

In Western Europe, the term Eastern Bloc generally referred to the USSR and Central and Eastern European countries in the Comecon (East Germany, Poland, Czechoslovakia, Hungary, Romania, Bulgaria, and Albania). In Asia, the Eastern Bloc comprised Mongolia, Vietnam, Laos, Kampuchea, North Korea, South Yemen and China. In the Americas, the countries aligned with the Soviet Union included Cuba from 1961 and for limited periods Nicaragua and Grenada.

The Second World was one of the "Three Worlds" formed by the global political landscape of the Cold War, as it grouped together those countries that were aligned with the Eastern Bloc of the Soviet Union and allies in Warsaw Pact. This grouping was directly opposed to the First World, which similarly grouped together those countries that were aligned with the Western Bloc of the United States and allies in NATO. It included communist states that were originally under the Soviet sphere of influence, though some eventually broke away from the Soviet ideology (e.g., Yugoslavia's split and China's split) to develop their own path as socialist states while retaining their communist governments. Most communist states remained under Soviet influence until the Revolutions of 1989. In 1991, upon the dissolution of the Soviet Union, only five communist states remained: China, Cuba, Laos, North Korea, and Vietnam. Though the terms "First World" and "Third World" continue to see present-day relevance in colloquial speech, albeit with a repurposed definition, the term "Second World" is obsolete outside of a Cold War context.

The League of Communists of Yugoslavia, known until 1952 as the Communist Party of Yugoslavia, was the founding and ruling party of the Socialist Federal Republic of Yugoslavia. It was formed in 1919 as the main communist opposition party in the Kingdom of Serbs, Croats and Slovenes and after its initial successes in the elections, it was proscribed by the royal government and was at times harshly and violently suppressed. It remained an illegal underground group until World War II when, after the invasion of Yugoslavia in 1941, the military arm of the party, the Yugoslav Partisans, became embroiled in a bloody civil war and defeated the Axis powers and their local auxiliaries. After the liberation from foreign occupation in 1945, the party consolidated its power and established a one-party state, which existed in that form of government until 1990, a year prior to the start of the Yugoslav Wars and breakup of Yugoslavia.

Led by Josip Broz Tito from 1937 to 1980, it was the first communist party in power to defy the Soviet hegemony in the Eastern Bloc and thus was expelled from the Cominform in 1948 in what is known as the Tito–Stalin split. After internal purges of pro-Soviet members, the party renamed itself the League of Communists in 1952 and adopted the politics of workers' self-management and an independent path to achieving socialism, known as Titoism.

Titoism is a socialist political philosophy most closely associated with Josip Broz Tito and refers to the ideology and policies of the League of Communists of Yugoslavia (LCY) during the Cold War. It is characterized by a broad Yugoslav identity, socialist workers' self-management, a political separation from the Soviet Union, and leadership in the Non-Aligned Movement.

Tito led the communist Yugoslav Partisans during World War II in Yugoslavia. After the war, tensions arose between Yugoslavia and the Soviet Union. Although these issues alleviated over time, Yugoslavia still remained largely independent in ideology and policy due to the leadership of Tito, who led Yugoslavia until his death in 1980.