The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a
transcontinental country
This is a list of countries with territory that straddles more than one continent, known as transcontinental states or intercontinental states.
Contiguous transcontinental countries are states that have one continuous or immediately-adjace ...
that spanned much of
Eurasia
Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelag ...
from 1922 to 1991. A flagship
communist state
A communist state, also known as a Marxist–Leninist state, is a one-party state that is administered and governed by a communist party guided by Marxism–Leninism. Marxism–Leninism was the Ideology of the Communist Party of the Soviet U ...
, it was nominally a
federal union
A federation (also known as a federal state) is a political entity characterized by a union of partially self-governing provinces, states, or other regions under a central federal government (federalism). In a federation, the self-govern ...
of
fifteen national republics; in practice, both
its government and
its economy were highly
centralized
Centralisation or centralization (see spelling differences) is the process by which the activities of an organisation, particularly those regarding planning and decision-making, framing strategy and policies become concentrated within a partic ...
until its final years. It was a
one-party state
A one-party state, single-party state, one-party system, or single-party system is a type of sovereign state in which only one political party has the right to form the government, usually based on the existing constitution. All other parties ...
governed by the
Communist Party of the Soviet Union, with the city of
Moscow
Moscow ( , US chiefly ; rus, links=no, Москва, r=Moskva, p=mɐskˈva, a=Москва.ogg) is the capital and largest city of Russia. The city stands on the Moskva River in Central Russia, with a population estimated at 13.0 million ...
serving as its capital as well as that of its largest and most populous republic: the
Russian SFSR
The Russian Soviet Federative Socialist Republic, Russian SFSR or RSFSR ( rus, Российская Советская Федеративная Социалистическая Республика, Rossíyskaya Sovétskaya Federatívnaya Soci ...
. Other major cities included
Leningrad
Saint Petersburg ( rus, links=no, Санкт-Петербург, a=Ru-Sankt Peterburg Leningrad Petrograd Piter.ogg, r=Sankt-Peterburg, p=ˈsankt pʲɪtʲɪrˈburk), formerly known as Petrograd (1914–1924) and later Leningrad (1924–1991), i ...
(Russian SFSR),
Kiev
Kyiv, also spelled Kiev, is the capital and most populous city of Ukraine. It is in north-central Ukraine along the Dnieper River. As of 1 January 2021, its population was 2,962,180, making Kyiv the seventh-most populous city in Europe.
Ky ...
(
Ukrainian SSR
The Ukrainian Soviet Socialist Republic ( uk, Украї́нська Радя́нська Соціалісти́чна Респу́бліка, ; russian: Украи́нская Сове́тская Социалисти́ческая Респ ...
),
Minsk
Minsk ( be, Мінск ; russian: Минск) is the capital and the largest city of Belarus, located on the Svislach (Berezina), Svislach and the now subterranean Nyamiha, Niamiha rivers. As the capital, Minsk has a special administrative stat ...
(
Byelorussian SSR
The Byelorussian Soviet Socialist Republic (BSSR, or Byelorussian SSR; be, Беларуская Савецкая Сацыялістычная Рэспубліка, Bielaruskaja Savieckaja Sacyjalistyčnaja Respublika; russian: Белор� ...
),
Tashkent
Tashkent (, uz, Toshkent, Тошкент/, ) (from russian: Ташкент), or Toshkent (; ), also historically known as Chach is the capital and largest city of Uzbekistan. It is the most populous city in Central Asia, with a population of ...
(
Uzbek SSR
Uzbekistan (, ) is the common English language, English name for the Uzbek Soviet Socialist Republic (Uzbek SSR; uz, Ўзбекистон Совет Социалистик Республикаси, Oʻzbekiston Sovet Sotsialistik Respublikasi, ...
),
Alma-Ata
Almaty (; kk, Алматы; ), formerly known as Alma-Ata ( kk, Алма-Ата), is the largest city in Kazakhstan, with a population of about 2 million. It was the capital of Kazakhstan from 1929 to 1936 as an autonomous republic as part of ...
(
Kazakh SSR
; kk, Қазақ Советтік Социалистік Республикасы)
*1991: Republic of Kazakhstan (russian: Республика Казахстан; kk, Қазақстан Республикасы)
, linking_name = the ...
), and
Novosibirsk
Novosibirsk (, also ; rus, Новосиби́рск, p=nəvəsʲɪˈbʲirsk, a=ru-Новосибирск.ogg) is the largest city and administrative centre of Novosibirsk Oblast and Siberian Federal District in Russia. As of the 2021 Census, ...
(Russian SFSR). It was the largest country in the world, covering over and spanning
eleven time zones.
The country's roots lay in the
October Revolution
The October Revolution,. officially known as the Great October Socialist Revolution. in the Soviet Union, also known as the Bolshevik Revolution, was a revolution in Russia led by the Bolshevik Party of Vladimir Lenin that was a key mome ...
of 1917, when the
Bolsheviks
The Bolsheviks (russian: Большевики́, from большинство́ ''bol'shinstvó'', 'majority'),; derived from ''bol'shinstvó'' (большинство́), "majority", literally meaning "one of the majority". also known in English ...
, under the leadership of
Vladimir Lenin
Vladimir Ilyich Ulyanov. ( 1870 – 21 January 1924), better known as Vladimir Lenin,. was a Russian revolutionary, politician, and political theorist. He served as the first and founding head of government of Soviet Russia from 1917 to 1 ...
, overthrew the
Russian Provisional Government
The Russian Provisional Government ( rus, Временное правительство России, Vremennoye pravitel'stvo Rossii) was a provisional government of the Russian Republic, announced two days before and established immediatel ...
that had
earlier replaced the
House of Romanov
The House of Romanov (also transcribed Romanoff; rus, Романовы, Románovy, rɐˈmanəvɨ) was the reigning imperial house of Russia from 1613 to 1917. They achieved prominence after the Tsarina, Anastasia Romanova, was married to t ...
of the
Russian Empire
The Russian Empire was an empire and the final period of the List of Russian monarchs, Russian monarchy from 1721 to 1917, ruling across large parts of Eurasia. It succeeded the Tsardom of Russia following the Treaty of Nystad, which ended th ...
. The Bolshevik coup led to the establishment of the Russian Soviet Republic, the world's first constitutionally guaranteed
socialist state
A socialist state, socialist republic, or socialist country, sometimes referred to as a workers' state or workers' republic, is a sovereign state constitutionally dedicated to the establishment of socialism. The term ''communist state'' is ofte ...
. Persisting internal tensions escalated into the
Russian Civil War
{{Infobox military conflict
, conflict = Russian Civil War
, partof = the Russian Revolution and the aftermath of World War I
, image =
, caption = Clockwise from top left:
{{flatlist,
*Soldiers ...
. By 1922 the Bolsheviks under
Vladimir Lenin
Vladimir Ilyich Ulyanov. ( 1870 – 21 January 1924), better known as Vladimir Lenin,. was a Russian revolutionary, politician, and political theorist. He served as the first and founding head of government of Soviet Russia from 1917 to 1 ...
had emerged victorious, forming the Soviet Union. Following
Lenin's death
On 21 January 1924, at 18:50 EET, Vladimir Lenin, leader of the October Revolution and the first leader and founder of the Soviet Union, died in Gorki aged 53 after falling into a coma. The official cause of death was recorded as an incurable ...
in 1924,
Joseph Stalin
Joseph Vissarionovich Stalin (born Ioseb Besarionis dze Jughashvili; – 5 March 1953) was a Georgian revolutionary and Soviet political leader who led the Soviet Union from 1924 until his death in 1953. He held power as General Secreta ...
came to power. Stalin inaugurated a period of
rapid industrialization and
forced collectivization that led to significant economic growth, but also contributed to a
famine in 1930–1933 that killed millions. The
labour camp
A labor camp (or labour camp, see spelling differences) or work camp is a detention facility where inmates are forced to engage in penal labor as a form of punishment. Labor camps have many common aspects with slavery and with prisons (espec ...
system of the
Gulag
The Gulag, an acronym for , , "chief administration of the camps". The original name given to the system of camps controlled by the State Political Directorate, GPU was the Main Administration of Corrective Labor Camps (, )., name=, group= ...
was also expanded in this period. Stalin conducted the
Great Purge
The Great Purge or the Great Terror (russian: Большой террор), also known as the Year of '37 (russian: 37-й год, translit=Tridtsat sedmoi god, label=none) and the Yezhovshchina ('period of Yezhov'), was Soviet General Secreta ...
to remove his actual and perceived opponents. After the outbreak of
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...
, Germany
invaded the Soviet Union. The combined
Soviet civilian and military casualty count—estimated to be around 27 million people—accounted for the majority of losses of
Allied forces. In the
aftermath of World War II
The aftermath of World War II was the beginning of a new era started in late 1945 (when World War II ended) for all countries involved, defined by the decline of all colonial empires and simultaneous rise of two superpowers; the Soviet Union (U ...
, the territory taken by the Red Army formed various
Soviet satellite states
A satellite state or dependent state is a country that is formally independent in the world, but under heavy political, economic, and military influence or control from another country. The term was coined by analogy to planetary objects orbitin ...
.
The beginning of the
Cold War saw the
Eastern Bloc
The Eastern Bloc, also known as the Communist Bloc and the Soviet Bloc, was the group of socialist states of Central and Eastern Europe, East Asia, Southeast Asia, Africa, and Latin America under the influence of the Soviet Union that existed du ...
of the Soviet Union confront the
Western Bloc
The Western Bloc, also known as the Free Bloc, the Capitalist Bloc, the American Bloc, and the NATO Bloc, was a coalition of countries that were officially allied with the United States during the Cold War of 1947–1991. It was spearheaded b ...
of the
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...
, with the latter grouping becoming largely uni