Proletarian internationalism, sometimes referred to as international socialism, is the perception of all proletarian revolutions as being part of a single global class struggle rather than separate localized events. It is based on the theory that capitalism is a world-system and therefore the working classes of all nations must act in concert if they are to replace it with communism.
Proletarian internationalism was strongly embraced by the first communist party, the Communist League, as exercised through its slogan "Proletarians of all countries, unite!", later popularized as "Workers of the world, unite!" in English literature. This notion was also embraced by the Bolshevik Party. After the formation of the Soviet Union, Marxist proponents of internationalism suggested that country could be used as a "homeland of communism" from which revolution could be spread around the globe. Though world revolution continued to figure prominently in Soviet rhetoric for decades, it no longer superseded domestic concerns on the government's agenda, especially after the ascension of Joseph Stalin, who was a proponent of socialism in one country. Despite this, the Soviet Union continued to foster international ties with communist and left-wing parties and governments around the world. It played a fundamental role in the establishment of several socialist states in Eastern Europe after World War II and backed the creation of others in Asia, Latin America, and Africa. The Soviets also funded dozens of insurgencies being waged against colonialist governments by leftist guerrilla movements worldwide. A few other states later exercised their own commitments to the cause of world revolution. Cuba frequently dispatched internationalist military missions abroad to defend communist interests in Africa and the Caribbean.
