1917

April — Lenin and other rev­o­lu­tion­ar­ies return to Rus­sia from Germany.

1917

Octo­ber — Bol­she­viks over­throw pro­vi­sional gov­ern­ment led by Alexan­der Keren­sky, with work­ers and sailors cap­tur­ing gov­ern­ment build­ings and the Win­ter Palace in St Peters­burg, and even­tu­ally tak­ing over Moscow.

Civil war

1918

- Treaty of Brest-Litovsk accord­ing to which Rus­sia ceded large tracts of land to Ger­many; Fin­land, Esto­nia, Latvia, Lithua­nia, Ukraine, Geor­gia, Arme­nia and Azer­bai­jan pro­claim their inde­pen­dence from Russia.

1918 – 20

- Civil war between Bol­she­viks, or Reds, and anti-Bolsheviks, or Whites, rav­ages Rus­sia. In north­ern Rus­sia, British, French and US troops cap­ture Mur­mansk and Archangel until 1919, while in the Russ­ian Far East they occupy Vladi­vos­tok, which was held by the Japan­ese until 1922.

1918 – 21

- Pol­icy of “war com­mu­nism” enun­ci­ated, with the state tak­ing con­trol of the whole econ­omy; mil­lions of peas­ants in the Don region starve to death as the army con­fis­cates grain for its own needs and the needs of urban dwellers.

1920

- War with Poland.

1921

- Peace treaty with Poland signed.

1921

- New Eco­nomic Pol­icy ush­ers in a par­tial return to the mar­ket econ­omy and a period of stability.

Col­lec­tivi­sa­tion and purges

1922

- Union treaty for­mally joins Rus­sia, Ukraine, Belarus and the Tran­scau­ca­sus — which were divided in 1936 into Geor­gia, Arme­nia and Azer­bai­jan — into the Soviet Union.

1922

- Ger­many recog­nises the Soviet Union.

1924

- Soviet Union adopts con­sti­tu­tion based on the dic­ta­tor­ship of the pro­le­tariat and stip­u­lat­ing the pub­lic own­er­ship of land and the means of pro­duc­tion; Lenin dies and is replaced by Joseph Stalin.

1928

- Adop­tion of first Five-Year Plan, with the state set­ting goals and pri­or­i­ties for the whole econ­omy, sig­ni­fies the end of the New Eco­nomic Policy.

Col­lec­tivi­sa­tion of agri­cul­ture begins; numer­ous rel­a­tively pros­per­ous peas­ants, or Kulaks, killed; mil­lions of peas­ant house­holds elim­i­nated and their prop­erty confiscated.

1936 – 38

- Announce­ment of the dis­cov­ery of a plot against Stalin’s regime headed by Leon Trot­sky ush­ers in a large-scale purge in which thou­sands of alleged dis­si­dents in the armed forces, the Com­mu­nist Party and the gov­ern­ment were sen­tenced to death or long imprisonment.

1933

- United States recog­nises the Soviet Union.

1934

- Soviet Union admit­ted to League of Nations.

1939

August — Soviet Union and Nazi Ger­many con­clude a non-aggression pact; Ger­many invades Poland, trig­ger­ing World War II.

1939

Sep­tem­ber — Soviet troops enter Poland, which is then divided between Ger­many and the USSR.

1939 – 40

- Russian-Finnish war, which ends with Fin­land ced­ing ter­ri­tory to the USSR — the present Russ­ian con­stituent repub­lic of Karelia.

World War II and its aftermath

1940

- Soviet troops occupy and Lithua­nia, Latvia and Esto­nia, which are then incor­po­rated into the USSR; Roma­nia cedes Bessara­bia and North Bukov­ina to the USSR which declares the Mol­da­vian Soviet Social­ist Repub­lic — the present inde­pen­dent repub­lic of Moldova.

1941

April — Soviet Union and Japan sign a non-aggression pact.

1941

June — Ger­many invades the USSR and by the end of the year occu­pies Belarus and most of Ukraine, sur­rounds Leningrad (now called St Peters­burg). Although a Soviet counter-offensive saves Moscow, by June 1942 the Ger­mans were on the gates of Stal­in­grad (now called Vol­gograd) and close to the Cau­ca­sus oil fields.

1943

- Ger­mans fail to take Stal­in­grad; Soviet troops launch a gen­eral counter-offensive which even­tu­ally cul­mi­nates in the cap­ture of Berlin in May 1945.

1945

- Soviet Union and the Allies reach under­stand­ing on post­war spheres of influ­ence in Europe dur­ing the Yalta and Post­dam sum­mit conferences.

1945

August — Soviet Union declares war on Japan, even­tu­ally annex­ing the south­ern half of Sakhalin and the Kuril islands.

1948 – 49

- Berlin block­ade: Soviet Union fails to pre­vent sup­plies from reach­ing the sec­tors of Berlin occu­pied by West­ern forces.

1949

- Soviet Union explodes its first atomic device; recog­nises the Com­mu­nist gov­ern­ment in China.

1950

- Soviet Union and China sign 30-year alliance treaty.

1950 – 53

- Out­break of Korean war sees rela­tions between the Soviet Union and the West dete­ri­o­rate markedly.

1953

March — Stalin dies and is suc­ceeded by Georgi Malenkov as prime min­is­ter and by Nikita Khrushchev as first sec­re­tary of the Cen­tral Com­mit­tee of the Com­mu­nist Party.

1953

- Soviet Union explodes its first hydro­gen bomb.

1955

- Niko­lay Bul­ganin replaces Malenkov as prime minister.

1955

- War­saw Treaty Organ­i­sa­tion, or War­saw Pact, set up.

1956

- Soviet troops help crush upris­ing in Hungary.

Post-Stalin thaw

1956

Feb­ru­ary — Khrushchev makes a secret speech to the 20^th Com­mu­nist Party con­gress denounc­ing Stalin’s dic­ta­to­r­ial rule and cult of personality.

1957

- First-ever arti­fi­cial earth satel­lite, Sput­nik, orbits the earth.

1958

- Khrushchev becomes prime min­is­ter — in addi­tion to Com­mu­nist Party chief — after dis­miss­ing Bulganin.

Late 1950s

- China falls out with the Soviet Union over Moscow’s pol­icy of peace­ful coex­is­tence with the West.

1960

- Soviet Union shoots down US spy plane U-2 over Soviet territory.

1961

- Yuri Gagarin makes the first manned orbital flight.

1962

- Cuban mis­sile cri­sis erupts over pres­ence of Soviet mis­siles in Cuba.

1963

- Soviet Union joins the US and Britain in sign­ing a treaty ban­ning atmos­pheric nuclear tests; US-Soviet “hot line” set up.

The Brezh­nev era

1964

- Khrushchev is replaced as first sec­re­tary of the Com­mu­nist Party by Leonid Brezh­nev; Alek­sey Kosy­gin becomes prime minister.

1968

- Soviet and War­saw Pact troops invade Czecho­slo­va­kia to stem a trend towards lib­er­al­i­sa­tion; “Brezh­nev doc­trine” enun­ci­ated, giv­ing com­mu­nist coun­tries the right to inter­vene in other com­mu­nist states whose poli­cies threat­ened the inter­na­tional com­mu­nist movement.

1969

- Soviet and Chi­nese troops clash across the border.

1972

- Soviet Union and US sign SALT-1 arms con­trol agree­ment, herald­ing the start of detente.

1974

- Soviet Union agrees to ease its emi­gra­tion pol­icy in return for most-favoured-nation trade sta­tus with the US.

1977

- Brezh­nev elected pres­i­dent under new constitution.

1979

- Soviet Union and US sign SALT-2 agree­ment; Soviet troops invade Afghanistan, for­mally end­ing the period of detente with the West.

1980

- Kosy­gin is replaced as prime min­is­ter by Niko­lay Tikhonov; Kosy­gin dies.

1982

- Brezh­nev dies and is replaced by KGB chief Yuri Andropov.

1984

- Andropov dies and is replaced by Kon­stan­tin Chernenko.

Glas­nost, per­e­stroika and Chernobyl

1985

- Cher­nenko dies and is replaced by Mikhail Gor­bachev as gen­eral sec­re­tary of the Com­mu­nist Party; Andrey Gromyko becomes pres­i­dent. Gor­bachev begins an anti-alcohol cam­paign and pro­mul­gates the poli­cies of open­ness, or glas­nost, and restruc­tur­ing, or perestroika.

1986

- Cher­nobyl nuclear power sta­tion explodes, show­er­ing large areas in Ukraine, Belarus and beyond with radioac­tive material.

1987

- Soviet Union and US agree to scrap intermediate-range nuclear mis­siles; Boris Yeltsin dis­missed as Moscow party chief for crit­i­cis­ing slow pace of reforms.

1988

- Gor­bachev replaces Gromyko as pres­i­dent; chal­lenges nation­al­ists in Kaza­khstan, the Baltic republics, Arme­nia and Azer­bai­jan; spe­cial Com­mu­nist Party con­fer­ence agrees to allow pri­vate sector.

1989

- Soviet troops leave Afghanistan; nation­al­ist riots put down in Geor­gia; Lithuan­ian Com­mu­nist Party declares its inde­pen­dence from the Soviet Com­mu­nist Party; first openly-contested elec­tions for new Con­gress of People’s Deputies, or parliament.

Death of the Soviet Union

1990

- Soviet troops sent to Azer­bai­jan fol­low­ing inter-ethnic killings between Arme­ni­ans and Azeris; Com­mu­nist Party votes to end one-party rule; Gor­bachev opposes inde­pen­dence of Baltic states and imposes sanc­tions on Lithua­nia; Yeltsin elected pres­i­dent of the Russ­ian Soviet Fed­er­a­tive Social­ist Repub­lic by the latter’s par­lia­ment and leaves the Soviet Com­mu­nist Party.

1991

August — Senior offi­cials, includ­ing Defence Min­is­ter Dmitry Yazov, Vice-President Gen­nadiy Yanayev and the heads of the Inte­rior Min­istry and the KGB detain Gor­bachev at his hol­i­day villa in Crimea, but are them­selves arrested after three days; Yeltsin bans the Soviet Com­mu­nist Party in Rus­sia and seizes its assets; Yeltsin recog­nises the inde­pen­dence of the Baltic republics; Ukraine, fol­lowed by other republics, declares itself independent.

1991

Sep­tem­ber — Con­gress of People’s Deputies votes for the dis­so­lu­tion of the Soviet Union.

1991

8 Decem­ber — Lead­ers of Rus­sia, Ukraine and Belarus sign agree­ment set­ting up Com­mon­wealth of Inde­pen­dent States.

1991

25 Decem­ber — Gor­bachev resigns as Soviet pres­i­dent; US recog­nises inde­pen­dence of remain­ing Soviet republics.

1991

26 Decem­ber — Russ­ian gov­ern­ment takes over offices of USSR in Russia.