Political situation in Europe during the Cold War
The "three worlds
" of the Cold War era between April–August 1975:
The Eastern Bloc (also the Socialist Bloc, the Communist Bloc, and the Soviet Bloc) was the group of communist states of Central and Eastern Europe, East Asia, and Southeast Asia under the hegemony of the Soviet Union (USSR) during the Cold War (1947–1991) in opposition to the capitalist Western Bloc. Generally, in Western Europe the term Eastern Bloc referred to the USSR and its East European satellite states in the Comecon (East Germany, Poland, Czechoslovakia, Hungary, Romania, Bulgaria, and Albania); in Asia, the Soviet Bloc comprised the Mongolian People's Republic, the Socialist Republic of Vietnam, the Lao People's Democratic Republic and the People's Republic of Kampuchea, the Democratic People's Republic of Korea, and the People's Republic of China (before the Sino-Soviet split in 1961). In the Americas, the Communist Bloc included the Caribbean Republic of Cuba, since 1961.
Soviet control of the Eastern Bloc was tested by the 1948 Czechoslovak coup d'état and the Tito–Stalin Split over the direction of the People's Federal Republic of Yugoslavia, the Chinese Communist Revolution (1949), and China's participation in the Korean War. After Stalin's death in 1953, the Korean War ceased with the 1954 Geneva Conference. In Europe, anti-Soviet sentiment provoked the Uprising of 1953 in East Germany. The break-up of the Eastern Bloc began in 1956 with Nikita Khrushchev's anti-Stalinist speech On the Cult of Personality and Its Consequences. This speech was a factor in the Hungarian Revolution of 1956, which the Soviet Union suppressed. The Sino–Soviet split gave North Korea and North Vietnam more independence from both and facilitated the Soviet–Albanian split. The Cuban Missile Crisis preserved the Cuban Revolution from rollback by the United States, but Fidel Castro became increasingly independent of Soviet influence afterwards, most notably during the 1975 Cuban intervention in Angola. That year, the communist victory in former French Indochina following the end of the Vietnam War gave the Eastern Bloc renewed confidence after it had been frayed by Soviet leader Leonid Brezhnev's 1968 invasion of Czechoslovakia to suppress the Prague Spring. This led to the People's Republic of Albania withdrawing from the Warsaw Pact, briefly aligning with Mao Zedong's China until the Sino-Albanian split.
Under the Brezhnev Doctrine, the Soviet Union reserved the right to intervene in other socialist states. In response, China moved towards the United States following the Sino-Soviet border conflict and later reformed and liberalized its economy while the Eastern Bloc saw the Era of Stagnation in comparison with the capitalist First World. The Soviet–Afghan War nominally expanded the Eastern Bloc, but the war proved unwinnable and too costly for the Soviets, challenged in Eastern Europe by the civil resistance of Solidarity. In the late 1980s, Soviet leader Mikhail Gorbachev pursued policies of glasnost ("openness") and perestroika ("restructuring") to reform the Eastern Bloc and end the Cold War, which brought forth unrest throughout the bloc. Unlike previous Soviet leaders in 1953, 1956, and 1968, Gorbachev refused to use force to end the 1989 Revolutions against Marxist–Leninist rule in Eastern Europe. The fall of the Berlin Wall and end of the Warsaw Pact spread nationalist and liberal ideals throughout the Soviet Union, which would soon dissolve at the end of 1991. Conservative communist elites launched a 1991 Soviet coup d'état attempt, which hastened the end of Marxist–Leninist rule in Eastern Europe. The 1989 Tiananmen Square protests in China were violently repressed by the communist government there, which maintained its grip on power.
Although the Soviet Union and its rival the United States considered Europe to be the most important front of the Cold War, the term Eastern Bloc was often used interchangeably with the term Second World. This broadest usage of the term would include not only Maoist China and Cambodia, but short-lived Soviet satellites such as the Second East Turkestan Republic (1944–1949), the People's Republic of Azerbaijan, and Republic of Mahabad (1946), as well as the Marxist–Leninist states straddling the Second and Third Worlds before the end of the Cold War: the People's Democratic Republic of Yemen (from 1967), the People's Republic of the Congo (from 1969), the People's Republic of Benin, the People's Republic of Angola and People's Republic of Mozambique from 1975, the People's Revolutionary Government of Grenada from 1979 to 1983, the Derg/People's Democratic Republic of Ethiopia from 1974, and the Somali Democratic Republic from 1969 until the Ogaden War in 1977. Many states were also accused by the Western Bloc of being in the Eastern Bloc when they were actually part of the Non-Aligned Movement. The most limited definition of the Eastern Bloc would only include the Warsaw Pact states and the Mongolian People's Republic as former satellite states most dominated by the Soviet Union. However, North Korea was similarly subordinate before the Korean War and Soviet aid during the Vietnam War enabled Vietnam to dominate Laos and Cambodia until the end of the Cold War. Cuba's defiance of complete Soviet control was noteworthy enough that Cuba was sometimes excluded as a satellite state altogether, as it sometimes intervened in other Third World countries even when Moscow opposed this.
The only surviving communist states are China, Vietnam, Cuba, North Korea, and Laos. Their state socialist experience was more in line with decolonization from the Global North and anti-imperialism towards the West instead of the Red Army occupation of the former Eastern Bloc. The five surviving socialist states all adopted economic reforms to varying degrees. China and Vietnam are usually described as more state capitalist than the more traditionalist Cuba and Laos and the overtly Stalinist North Korea. Cambodia and Kazakhstan are still led by the same Eastern Bloc leaders as during the Cold War, though they are not officially Marxist–Leninist states. This was previously the case in Kazakhstan's fellow post-Soviet states of Uzbekistan until 2016, Turkmenistan until 2006, Kyrgyzstan until 2005, and Azerbaijan and Georgia until 2003. All presidents of post-Soviet Russia were members of the Communist Party of the Soviet Union (Boris Yeltsin before 1990, Vladimir Putin and Dmitry Medvedev before 1991). Azerbaijan is an authoritarian dominant-party state and North Korea is a totalitarian one-party state led by the heirs of their Eastern Bloc leaders, yet both have officially eliminated mentions of communism from their constitutions.
Post-1991 usage of the term "Eastern Bloc" may be more limited in referring to the states forming the Warsaw Pact (1955–1991) and Mongolia (1924–1992), which are no longer communist states. Sometimes they are more generally referred to as "the countries of Eastern Europe under communism", excluding Mongolia, but including Yugoslavia and Albania which had both split with the Soviet Union by the 1960s.
Prior to the common use of the term, in the 1920s "Eastern Bloc" was used to refer to a loose alliance of eastern and central European countries.
Even though Yugoslavia was a socialist country, it was not a member of COMECON or the Warsaw Pact. Parting with the USSR in 1948, Yugoslavia did not belong to the East, but it also did not belong to the West because of its socialist system and its status as a founding member of the Non-Aligned Movement. However, many sources consider Yugoslavia to be a member of the Eastern Bloc. Others consider Yugoslavia not to be a member after it broke with Soviet policy in the 1948 Tito–Stalin split.