Soviet Russia

Following the October Revolution, a civil war broke out between the anti-communist White movement and the new Soviet regime with its Red Army. Russia lost its Ukrainian, Polish, Baltic, and Finnish territories by signing the Treaty of Brest-Litovsk that concluded hostilities with the Central Powers in World War I. The Allied powers launched an unsuccessful military intervention in support of anti-Communist forces, while both the Bolsheviks and White movement carried out campaigns of deportations and executions against each other, known respectively as the Red Terror and White Terror. By the end of the civil war, the Russian economy and infrastructure were heavily damaged. Millions became White émigrés, and the Povolzhye famine of 1921 claimed up to 5 million victims.

The Russian Soviet Federative Socialist Republic (called Russian Socialist Federative Soviet Republic at the time) together with the Ukrainian, Byelorussian, and Transcaucasion Soviet Socialist Republics, formed the Union of Soviet Socialist Republics (USSR), or Soviet Union, on 30 December 1922. Out of the 15 total republics that would make up the USSR, the Russian SFSR was the largest in terms of size, and making up over half of the total USSR population, dominated the union for its entire 69-year history.

Following Lenin's death in 1924, a troika had been designated to govern the Soviet Union. However, Joseph Stalin, an elected General Secretary of the Communist Party, managed to put down all opposition groups within the party and consolidate much power in his hands. Leon Trotsky, the main proponent of the world revolution, was exiled from the Soviet Union in 1929, and Stalin's idea of Socialism in One Country became the primary line. The continued internal struggle in the Bolshevik party culminated in the Great Purge, a period of mass repressions in 1937–38, in which hundreds of thousands of people were executed, including original party members and military leaders convicted in coup d'état plots.

Under Stalin's leadership, the government launched a planned economy, industrialisation of the largely rural country, and collectivization of its agriculture. During this period of rapid economical and social changes, millions of people were sent to penal labor camps, including many political convicts who opposed Stalin's rule, and millions were deported and exiled to remote areas of the Soviet Union. The transitional disorganisation of the country's agriculture, combined with the harsh state policies and a drought, led to the Soviet famine of 1932–1933. However, though with a heavy price, the Soviet Union was transformed from a largely agrarian economy to a major industrial powerhouse in a short span of time.

The Appeasement policy of Great Britain and France towards Adolf Hitler's annexations of Ruhr, Austria and finally of Czechoslovakia enlarged the might of Nazi Germany and put a threat of war to the Soviet Union. Around the same time the German Reich allied with the Empire of Japan, a rival of the USSR in the Far East and an open enemy in the Soviet–Japanese Border Wars in 1938–39.

In August 1939, after another failure of attempts to establish a counter-Nazism alliance with Britain and France, and after Western powers had engaged in the policy of Appeasement with Nazi Germany, the Soviet government finally agreed to establish peaceful relations by concluding the Molotov-Ribbentrop Pact, pledging non-aggression between the two countries and dividing their spheres of influence in Eastern Europe. While Hitler conquered Poland, France and other countries acting on single front at the start of World War II, the USSR was able to build up its military and regain some of the former territories of the Russian Empire during the Soviet invasion of Poland and the Winter War.

On 22 June 1941, Nazi Germany broke the non-aggression treaty and invaded the Soviet Union with the largest and most powerful invasion force in human history, opening the largest theater of World War II. Although the German army had considerable success early on, their onslaught was halted in the Battle of Moscow. Subsequently the Germans were dealt major defeats first at the Battle of Stalingrad in the winter of 1942–43, and then in the Battle of Kursk in the summer of 1943. Another German failure was the Siege of Leningrad, in which the city was fully blockaded on land between 1941–44 by German and Finnish forces, suffering starvation and more than a million deaths, but never surrendering. Under Stalin's administration and the leadership of such commanders as Georgy Zhukov and Konstantin Rokossovsky, Soviet forces drove through Eastern Europe in 1944–45 and captured Berlin in May 1945. In August 1945 the Soviet Army ousted Japanese from China's Manchukuo and North Korea, contributing to the allied victory over Japan.

The 1941–45 period of World War II is known in Russia as the Great Patriotic War. In this conflict, which included many of the most lethal battle operations in human history, Soviet military and civilian deaths were 10.6 million and 15.9 million respectively, accounting for about a third of all World War II casualties. The full demographic loss to the Soviet peoples was even greater. The Soviet economy and infrastructure suffered massive devastation but the Soviet Union emerged as an acknowledged superpower.

The Red Army occupied Eastern Europe after the war, including East Germany. Dependent socialist governments were installed in the Eastern Bloc satellite states. Becoming the world's second nuclear weapons power, the USSR established the Warsaw Pact alliance and entered into a struggle for global dominance, known as the Cold War, with the United States and NATO. The Soviet Union supported revolutionary movements across the world, including the newly formed People's Republic of China, the Democratic People's Republic of Korea and, later on, the Republic of Cuba. Significant amounts of the Soviet resources were allocated in aid to the other socialist states.

After Stalin's death and a short period of collective rule, new leader Nikita Khrushchev denounced the cult of personality of Stalin and launched the policy of de-Stalinization. Penal labor system was reformed and many prisoners were released and rehabilitated (many of them posthumously). The general easement of repressive policies became known later as the Khrushchev Thaw. At the same time, tensions with the United States heightened when the two rivals clashed over the deployment of the U.S. Jupiter missiles in Turkey and Soviet missiles in Cuba.

In 1957 the Soviet Union launched the world's first artificial satellite, Sputnik 1, thus starting the Space Age. Russian cosmonaut Yuri Gagarin became the first human to orbit the Earth aboard Vostok 1 manned spacecraft on 12 April 1961.

Following the ousting of voluntarist and erratic Khrushchev in 1964, another period of collective rule ensued, until Leonid Brezhnev became the leader. The era of 1970s and the early 1980s was designated later as the Era of Stagnation, a period when the economic growth slowed and social policies became static. The 1965 Kosygin reform, aimed into partial decentralization of the Soviet economy and shifting the emphasis from heavy industry and weapons to light industry and consumer goods, was stifled by the conservative Communist leadership.

In 1979, after a Communist-led revolution in Afghanistan, Soviet forces entered the country by request of the new regime. The occupation drained economic resources and dragged on without achieving meaningful political results. Ultimately the Soviet Army was withdrawn from Afghanistan in 1989 because of international opposition, persistent anti-Soviet guerilla warfare (enhanced by the U.S.), and a lack of support from Soviet citizens.

From 1985 onwards, the last Soviet leader Mikhail Gorbachev, who sought to enact liberal reforms in the Soviet system, introduced the policies of glasnost (openness) and perestroika (restructuring) in an attempt to end the period of economic stagnation in the country and democratise the government. However, this led to the rise of strong nationalist and separatist movements. Prior to 1991, the Soviet economy was the second largest in the world, but during its last years it was afflicted by shortages of goods in grocery stores, huge budget deficits, and explosive growth in money supply leading to inflation.

By 1991, economic and political turmoil were beginning to boil over, as the Baltic republics chose to secede from the Union. On March 17, a referendum was held, to which the vast majority of participating citizens voted in favour of preserving the Soviet Union as a renewed federation. In August 1991, a coup d'état attempt by members of Gorbachev's government, directed against Gorbachev and aimed at preserving the Soviet Union, instead led to the end of the Communist Party of the Soviet Union. Despite the will expressed by the people, on 25 December 1991, the USSR was dissolved into 15 post-Soviet states.