1920 CE

The Prohibition era begins as the Eighteenth Amendment and Volstead Act ban alcohol across the United States, sparking speakeasies and organized crime; the League of Nations is established in Geneva, Switzerland to maintain global peace; the 1920 Summer Olympics are held in Antwerp, Belgium, introducing the Olympic flag and athlete's oath; the Battle of Warsaw turns the Polish–Soviet War in Poland's favor, repelling the Red Army; the Red Army invasion of Armenia and Red Army invasion of Azerbaijan bring both nations into the Soviet Union; and the Wall Street bombing kills 38 and injures hundreds in New York City's financial district.

In the 1920s, the 20th century.

1920 at a glance

World population: about 1.90 billion Our World in Data
United States: Woodrow Wilson (President) Wikipedia rev. 1377869146
United Kingdom: George V (King); David Lloyd George (Prime minister) Wikipedia rev. 1377869146
Russia: Vladimir Lenin (Premier) Wikipedia rev. 1377869146
Republic of China (1916–1949): Xu Shichang (President) Wikipedia rev. 1377869146
French Third Republic: Raymond Poincaré, then Paul Deschanel, then Alexandre Millerand (President); Georges Clemenceau, then Alexandre Millerand, then Georges Leygues (President of the Council of ministers) Wikipedia rev. 1377869146
Weimar Republic of Germany: Friedrich Ebert (President); Gustav Bauer, then Hermann Müller, then Constantin Fehrenbach (Chancellor) Wikipedia rev. 1377869146
$1 in 1920: $16.81 in September 2026 dollars BLS CPI-U

Who led every country in 1920 →Born in 1920? What it cost, who led, what was No. 1 →

Geopolitics & Diplomacy

January 15 – Paris Peace Conference presents peace terms to the Hungarian delegationHungary source
January 16 – The Allies of World War I demand that the Netherlands extradite ex-German Emperor Wilhelm II who fled there in 1918.source
January 21 – The final session of the Paris Peace Conference is held, even though peace treaties with Hungary and Turkey remain to be concluded. The United States does not conclude its own treaty with Germany until August 25, 1921.source
January 28 – El Tercio de Extranjeros (the "Regiment of Foreigners"), later the Spanish Legion, is established by decree of King Alfonso XIII of Spain.source
February 2 – Estonian War of Independence: The Tartu Peace Treaty is signed, ending the war and recognizing the independence of both the Republic of Estonia and the Russian Socialist Federative Soviet Republic.source
2 February – Treaty of Tartu which gave Estonia recognition by Soviet Russia.Estonia source
February 9 – The Svalbard Treaty, signed by members of the League of Nations in Paris, recognises the sovereignty of Norway over the Arctic archipelago of Svalbard (at this time called Spitzbergen), while giving the other signatories economic rights in the islands.source
February 24 – Adolf Hitler presents his National Socialist Program in Munich to the German Workers' Party (Deutsche Arbeiterpartei), which renames itself as the Nazi Party (Nationalsozialistische Deutsche Arbeiterpartei).source
March 10 – The world's first peaceful establishment of a social democratic government takes place in Sweden as Hjalmar Branting takes over as prime minister when Nils Edén leaves office.source
March 23 – Admiral Miklós Horthy declares that Hungary is a monarchy, without anyone on the throne.source
April 19–26 – San Remo conference: Representatives of Italy, France, the United Kingdom, and Japan meet to determine the League of Nations mandates for administration of territories, following the partitioning of the Ottoman Empire.source
April 20 – José de las Fuentes Rodríguez, lawyer and politician (PRI); Governor of Coahuila 1981–1987 (died 2011)Mexico source
April 26 – The Khorezm People's Soviet Republic is officially created by Soviet Russia, as the successor to the Khanate of Khiva.source
26 April – The San Remo conference ends, during which the Allied Supreme Council agree to allocate the mandate of Palestine to the United Kingdom, incorporating the terms set forth in the Balfour Declaration.British-administered Palestine source
May 10 – In the general election, the Rikken Seiyūkai, led by Prime Minister Hara Takashi, increases on its majority of seats in the lower house of the Diet.Japan source
June 4 – Treaty of Trianon: Peace is restored between the Allied Powers and Hungary, which loses 72% of its territory.source
4 June – The Treaty of Trianon is signed. Transylvania and most of Banat become part of Romania.Romania source
June 15 – The Estonian Constituent Assembly adopts the first constitution of Estonia, which will come into effect on December 21 this year.source
July 12 – Soviet–Lithuanian Peace Treaty: The Russian Soviet Federative Socialist Republic recognizes independent Lithuania.source
July 20 – The United Kingdom cedes its brief control of the key Black Sea port of Batum to the Democratic Republic of Georgia.source
July 31 – Representatives of British revolutionary socialist groups meet at the Cannon Street Hotel in London and agree to form the Communist Party of Great Britain.source
August 10 – Ottoman Sultan Mehmed VI's representatives sign the Treaty of Sèvres with the Allied Powers, confirming arrangements for the partitioning of the Ottoman Empire.source
September 8 – Gabriele D'Annunzio proclaims the Italian Regency of Carnaro in the city of Fiume.source
November 2 – 1920 United States presidential election: Republican U.S. senator Warren G. Harding defeats Democratic governor of Ohio James M. Cox and Socialist Eugene V. Debs, in the first national U.S. election in which women have the right to vote.source
15 November – The first convention of the League of Nations takes place in Geneva with 41 member states in attendance.Switzerland source
November 28 – FIDAC (French: Fédération Interalliée des Anciens Combattants, English: The Interallied Federation of War Veterans Organisations) is established in Paris at the initiative of veterans from World War I, predominantly pacifists, joined by associations of veterans from France, the United Kingdom, United States, Belgium, Romania, Czechoslovakia, Italy and Serbia.source
December 3 – Following more than a month of the Turkish–Armenian War, the Turkish-dictated Treaty of Alexandropol is concluded.source
December 7 – The first draft of the Mandate for Palestine is submitted to the League of Nations.source
December 10 – Irish War of Independence: Martial law is declared in Counties Cork, Kerry, Limerick and Tipperary by the British authorities.source
December 17 – South Africa is granted a League of Nations Class C mandate over South West Africa.source
December 23 – The Government of Ireland Act 1920, passed by the Parliament of the United Kingdom, receives Royal Assent from George V, providing for the partition of Ireland into Northern Ireland and Southern Ireland, with separate parliaments, granting a measure of home rule.source
Establishment of the Reconstitution Party.Portugal source

Conflict & Security

January 1 – Polish–Soviet War: The Russian Red Army increases its troops along the Polish border from 4 divisions to 20.source
January 7 – Russian Civil War: The forces of Russian White Admiral Alexander Kolchak surrender in Krasnoyarsk; the Great Siberian Ice March ensues.source
January 21 – Battle of Shekar Yazi.Iran source
February 24 – Nikolayevsk Incident: Realizing that he is outnumbered and far from reinforcement, the commander of the Japanese garrison allows Yakov Triapitsyn's troops to enter the town of Nikolayevsk-on-Amur under a flag of truce.Japan source
March 13–17 – Wolfgang Kapp and Walther von Lüttwitz's Kapp Putsch (an attempted coup in Germany) briefly ousts the Weimar Republic government from Berlin, but fails due to public resistance and a general strike.source
13 March – Kapp Putsch: Wolfgang Kapp and Walther von Lüttwitz attempt to overthrow the Weimar Republic and establish an autocratic government in its place.Germany source
March 15–16 – Constantinople is occupied by British Empire forces, acting for the Allied Powers against the Turkish National Movement. Retrospectively, the Grand National Assembly of Turkey regards this as the dissolution of the Ottoman regime in Istanbul.source
March 25 – Irish War of Independence: British recruits to the Royal Irish Constabulary begin to arrive in Ireland. They become known from their improvised uniforms as the "Black and Tans".source
Czechoslovak troops withdraw from (part of) Sátoraljaújhely to the Trianon borderHungary source
April 2 – The German army marches to the Ruhr to fight the Ruhr Red Army.source
April 3 – Failed assassination attempts on General Mannerheim, retired leader of the victorious White Guard in the Finnish Civil War, led by Aleksander Weckman by order of Eino Rahja, during a White Guard parade in Tampere, Finland.source
April 11 – Mexican Revolution: Álvaro Obregón flees from Mexico City (during a trial intended to ruin his reputation) to Guerrero, where he joins Fortunato Maycotte.source
April 19–26 – San Remo conference held at Castle Devachan in Sanremo, Italy. Representatives of Italy, France, the United Kingdom and Japan meet to determine the League of Nations mandates for administration of territories following partitioning of the Ottoman Empire. The conference was attended by the four Principal Allied Powers of World War I who were represented by the prime ministers of Britain (David Lloyd George), France (Alexandre Millerand), Italy (Francesco Nitti) and by Japan's Ambassador Keishirō Matsui.Italy source
April 23: Mexican Revolution: Plan of Agua Prieta is proclaimed; rebellion against Venustiano Carranza commences.Mexico source
April 24 – Polish–Soviet War: Polish and anti-Soviet Ukrainian troops attack the Red Army in Soviet Ukraine.source
4–7 April – Nebi Musa Riots in and around the Old City of Jerusalem mark the first large-scale skirmish of the Arab–Israeli conflict. Four Arabs and five Jews are killed, while 216 Jews (18 critically) and 23 Arabs (one critically) are wounded. The majority of the victims were members of the old Yishuv, largely non-Zionist or anti-Zionist Orthodox Jews. About 300 Jews from the Old City of Jerusalem are evacuated.British-administered Palestine source
May 7 – Polish–Soviet War: Polish troops occupy Kyiv. The government of the Ukrainian People's Republic returns to the city.source
May 26 – Ganja revolt: Anti-Soviet opposition in the Azerbaijan SSR launches an abortive revolt in Ganja.source
July 2 – Polish–Soviet War: The Red Army continues its offensive into Poland.source
July 19–August 7 – The Second Congress of the Communist International takes place in Saint Petersburg and Moscow; the Twenty-one Conditions are adopted.source
August 13 – Irish War of Independence: The Restoration of Order in Ireland Act (passed by the Parliament of the United Kingdom) receives Royal Assent, providing for Irish Republican Army activists to be tried by court-martial, rather than by jury in criminal courts.source
August 13–25 – Polish–Soviet War: Battle of Warsaw – The Red Army is defeated.source
August 19–25 – Second Silesian Uprising: The Poles in Upper Silesia rise up against the Germans.source
August 19 – Russian Civil War: Peasants in Tambov Governorate begin the Tambov Rebellion against the Bolshevik government of Soviet Russia.source
August 28–September 2 – Bukhara operation: The Russian Red Army and Young Bukharians overthrow the Emirate of Bukhara, leading to the establishment of the Bukharan People's Soviet Republic.source
September 16 – Wall Street bombing: A bomb in a horse wagon (perhaps planted by Galleanisti) explodes in front of the J. P. Morgan Building in New York City, killing 38 and injuring 400.source
September 20 – The first soldier joins El Tercio de Extranjeros (the "Regiment of Foreigners", later the Spanish Legion). Under the command of José Millán Astray and Francisco Franco, its first duties are against Rif rebels in the Spanish protectorate in Morocco.source
October 16 – Polish–Soviet War: After the Polish army captures Tarnopol, Dubno, Minsk and Dryssa, the ceasefire is enforced.source
November 13 – The White Army's last units and civilian refugees are evacuated from the Crimea onboard 126 ships, "Wrangel's fleet" (the remnants of the Imperial Russian Navy's Black Sea Fleet), to Turkey, Tunisia and the Kingdom of Serbs, Croats and Slovenes, accompanied by wide-scale civilian massacres. The total number of evacuees amounts to approximately 150,000 people, of which 20% are civilians.source
November 21 – Irish War of Independence: Bloody Sunday – The Irish Republican Army (IRA), on the instructions of Michael Collins, shoot dead the "Cairo gang", 14 British undercover agents in Dublin, most in their homes. Later this day in retaliation, the Auxiliary Division of the Royal Irish Constabulary open fire on a crowd at a Gaelic Athletic Association football match in Croke Park, resulting in 14 deaths with 60 wounded. Three men are shot this night in Dublin Castle "while trying to escape".source
November 28 – Irish War of Independence: Kilmichael Ambush – The flying column of the 3rd Cork Brigade of the Irish Republican Army, led by Tom Barry, ambushes two lorries carrying men of the Auxiliary Division of the Royal Irish Constabulary at Kilmichael, County Cork, killing 17 (with 3 of its own men also dying), which leads to official reprisals.source
Polish and allied Ukrainian forces capture Kiev in the Kiev offensive of the Polish-Soviet War (7 May)Russia source

Exploration & Expansion

29 April – Welwyn Garden City established by Ebenezer Howard. The first house is occupied just before Christmas.United Kingdom source
May 12 – Hungary presents its border proposal to the French government: they ask for all Hungarian-populated areas along the Trianon borders, referendums in the Banat and Burgenland, Carpathean Ruthenia and Eastern Slovakia for "economic reasons". The proposal was unacceptable for the French party, leading to the end of the secret negotiations.Hungary source
May 31 - The Rome–Tokyo Raid, a cross-Eurasian flight from Rome to Tokyo organized by Harukichi Shimoi and Gabrielle D'Annunzio ends with Arturo Ferrarin arriving in Tokyo.Japan source
10 August – The Princes Highway is officially opened.Australia source
25 August – Captain Euan Dickson makes the first aerial crossing of Cook Strait, from Christchurch to Upper Hutt, in an Avro 504K.New Zealand source
The founding of the kibbutz Degania Bet by immigrants from the Second Aliyah.British-administered Palestine source
The Aalesund ship is discovered embedded in the earth south of Ålesund.Norway source
Explorer Edgeworth David and civil servant George Lewis Barstow are knighted.Wales source

Religion & Belief

January 16 – Albert Apponyi speaks in front of the Paris Peace ConferenceHungary source
February 12–24 – Conference of London: Leaders of the United Kingdom, France and Italy meet to discuss the partitioning of the Ottoman Empire.source
9 April – The Times publishes a special "Belgian number" (pages 33-54) with contributions by many prominent Belgians.Belgium source
May 16 – Canonization of Joan of Arc: Over 30,000 people attend the ceremony in Rome, including 140 descendants of Joan of Arc's family. Pope Benedict XV presides over the rite, for which the interior of St. Peter's Basilica in Rome is richly decorated.source
June 2 – Francisco Plancarte y Navarrete, archaeologist and archbishop of Monterrey, 1911–1920 (born 1856)Mexico source
June – The Catholic Women's League is formed in Montreal.Canada source
17 July – Christopher Bruun, Norwegian priest and educator.Norway source
July 31 – Irish-born Australian Catholic Archbishop Daniel Mannix is detained on board ship by British authorities off Queenstown and prevented from landing in Ireland or from speaking in the main Irish Catholic communities elsewhere in the United Kingdom.source
September 12 – The position of Patriarch of the Serbs is re-established as the authority over the Serbian Orthodox Church, almost 156 years to the day after it was abolished by the Ottoman Empire in 1766.source
7 October - The establishment of the Jewish National Council, the main national institution of the Jewish community (Yishuv) within the British Mandate of Palestine.British-administered Palestine source
November 2 – Meiji Shrine, one of many landmark spots in Tokyo, is officially built in Japan.source
November 11 – In London, The Cenotaph is unveiled and The Unknown Warrior is buried in Westminster Abbey; while in Paris the Tomb of the Unknown Soldier is consecrated beneath the Arc de Triomphe.source
November 17 – The council of the League of Nations accepts the constitution for the Free City of Danzig.source
December 15–22 – The Brussels Conference establishes a timetable for German war reparations, intended to extend for over 42 years.source
December 25 – The Rosicrucian Fellowship's spiritual healing temple The Ecclesia is dedicated at Mount Ecclesia, Oceanside, California.source
The first edition of the Poems of the English war poet Wilfred Owen, killed in action in 1918, appears in London, introduced by his friend Siegfried Sassoon. Only five of Owen's verses having been published in his lifetime, the collection introduces his work to many readers. It includes the 1917 poems "Anthem for Doomed Youth" and "Dulce et Decorum est", two of the best-known poetic condemnations of war.source
Charitable and Religious Trusts ActIndia source
Monarch – Victor Emmanuel III (1900–1946)Italy source

Economy & Finance

January 1 – Kauniainen in Finland, completely surrounded by the city of Espoo, secedes from Espoo as its own market town.source
February 1 – The Royal North-West Mounted Police and the Dominion Police are amalgamated and renamed the Royal Canadian Mounted Police.Canada source
31 March – Charles David Murray is appointed Solicitor General for Scotland, replacing Thomas Brash Morison.Scotland source
18 May – Johan Henrik Paasche Thorne, businessperson and politician (born 1843)Norway source
June 16 – José López Portillo, president of Mexico (1970–1976)Mexico source
November 16 – Queensland and Northern Territory Aviation Services (Qantas) is founded by Hudson Fysh and Paul McGinness.source
December 13 – Confectionery company Haribo is founded in Bonn, Germany.source
December 16 – Bank of Yokohama was founded, as predecessor name was Yokohama Kōshō Bank (横浜興商銀行) in Kanagawa Prefecture.Japan source
17 December – The authority to issue currency notes is transferred from Treasury on the Australian Notes Board.Australia source
Estrela de Vendas Novas foundedPortugal source
Depression of 1920–21 (1920–1921)United States source

Technology & Infrastructure

February 1 – The South African Air Force (SAAF) is established, the second autonomous Air Force in the world, after the British Royal Air Force (RAF).source
February 1 – The South African Air Force (SAAF) is established, the second autonomous Air Force in the world after the Royal Air Force (RAF).South Africa source
February – The Kawanishi Engineering Works, predecessor of ShinMaywa, is founded in Hyogo-ku, Kobe.Japan source
March 1 – The United States Railroad Administration returns control of American railroads to its constituent railroad companies.source
April – Turin metal-workers, in particular at the Fiat plants, go on strike demanding recognition for their 'factory councils'. The 'factory councils' more and more saw themselves as the models for a new democratically controlled economy running industrial plants, instead of as a bargaining tool with employers.Italy source
11 May – Mataura railway station is destroyed by fire. A replacement railway station building opens the following year.New Zealand source
May 17 – The first flight of Dutch air company KLM, from Amsterdam to London, takes place.source
June 15 – Australian soprano Nellie Melba becomes history's first well-known performer to make a radio broadcast when she sings two arias as part of an experimental series of broadcasts from a studio at the Marconi Company's factory at Chelmsford in England.source
June 20 – Transport workers' unions declare an international boycott on HungaryHungary source
July 29 – The United States Bureau of Reclamation begins construction of the Link River Dam, as part of the Klamath Reclamation Project.source
July 29 – Rodolfo Acosta, television actorMexico source
August 20 – The first commercial radio station in the United States, 8MK (WWJ), begins operations in Detroit. It is owned by the Detroit News, the first U.S. radio station owned by a newspaper.source
September 29 – The first domestic radio sets come to stores in the United States; a Westinghouse radio costs $10.source
November 2 – In the United States, KDKA AM of Pittsburgh (owned by Westinghouse) starts broadcasting as a commercial radio station. The first broadcast is the results of the presidential election.source
16 November – The Queensland and Northern Territory Aerial Service, later known as Qantas, is founded in Winton.Australia source
Establishment of the Republic of China Air ForceChina source

Science & Discovery

January 13 – The New York Times ridicules American rocket scientist Robert H. Goddard, which it will rescind following the launch of Apollo 11 in 1969.source
January 13 – The New York Times ridicules the American rocket scientist Robert H. Goddard. (Decades later, on July 17, 1969, as the Apollo 11 crew head to the Moon, the newspaper will retract this editorial.)United States source
13 March – Scotland 3–0 Ireland (in Glasgow).Ireland source
March 18 – Greece begins using the Gregorian calendar.source
March 26 – American fiction writer F. Scott Fitzgerald makes his name with publication of This Side of Paradise.source
April 26 – The Winnipeg Falcons representing Canada beat Sweden 12–1 to win the gold medal for ice hockey at the 1920 Olympics in Antwerp.Canada source
May 1 – 1920 Major League Baseball season: The Brooklyn Robins and the Boston Braves play to a 1–1 tie in 26 innings, recording the longest single game in MLB history.United States source
May 7 – Mexican Revolution: Venustiano Carranza leaves Mexico City in a large train.source
21 July - Interallied Mission to Poland is launched.France source
New Zealand Trotting Cup – Reta PeterNew Zealand source
Steinar Schjøtt, philologist and lexicographer (born 1844)Norway source
Border Terrier first recognised as a dog breed by The Kennel Club.Scotland source

Health & Medicine

January 5 – 1920 United States census count begins. This becomes the first census to record a population exceeding 100 million, at 106,021,537. Because there are so many mixed-race persons and because so many Americans with some black ancestry appear white, the Census Bureau stops counting mixed-race peoples and the one-drop rule becomes the national legal standard.United States source
January 17 – Prohibition in the United States begins, with the Eighteenth Amendment to the Constitution which bans the sale of alcohol in all states.source
January 23 – The Netherlands refuses to extradite ex-German Emperor Wilhelm II; on May 15 he moves into Huis Doorn in the country where he remains permanently in exile until his death in 1941.source
February 1 – Japanese sugar plantation workers in Hawaii officially join a strike led by Filipinos and Hispanic workers.Japan source
March 28 – The 1920 Palm Sunday tornado outbreak hits the Great Lakes region and Deep South of the United States.source
June 13 – The United States Post Office Department rules that children may not be sent via parcel post.source
July 21 – The Troubles in Ulster (1920–1922) begin with 8,000 Catholic and Socialist workers driven from shipyards and industrial sites in Belfast.source
July 31 – France prohibits the sale or prescription of contraceptives.source
31 July - France prohibits the sale or prescription of contraceptives.France source
September 26 – Numerus Clausus quota passed, limiting nationalities in university admissions to their share in the population. In practice, this limits the admission of Jewish studentsHungary source
October 31 – Dr. Frederick Banting of Ontario first records his insight on how to isolate insulin for the treatment of diabetes; the first successful human trial of insulin will occur 15 months later.source
29 November – Rationing imposed during World War I ends when the restriction on availability of sugar is lifted by the Government.United Kingdom source
5 December – Scotland votes against prohibition generally, despite 40 districts voting in favour.Scotland source
The so-called Spanish flu pandemic ends with an estimated total of between seventeen and fifty million dead since 1918. It would be the last global pandemic until the 2009 swine flu pandemic almost 90 years later.source
Hydrocodone, a narcotic analgesic closely related to codeine, is first synthesized in Germany, by Carl Mannich and Helene Löwenheim.source
Approximate date – The HIV/AIDS pandemic almost certainly originates in Léopoldville, modern-day Kinshasa, the capital of the Belgian Congo.source
Francesco Saverio Nitti (1919–1920)Italy source
Legalization of Abortion (1920–1936)Russia source

Crime & Justice

January 9 – Thousands of onlookers watch as "The Human Fly" George Polley climbs New York City's Woolworth Building. He reaches the 30th floor when a policeman arrests him for climbing without a permit.United States source
January 14 – Chava Flores, musical chronicler Álbum de Oro de la Canción and composer (Dos horas de balazos and La tertulia) (died August 5, 1987)Mexico source
May 24 – Venustiano Carranza is buried in Mexico City; all of his mourning allies are arrested. Adolfo de la Huerta is elected provisional president.source
June 15 – Duluth lynchings: Three African American circus workers are sprung from jail, subjected to a kangaroo court and hanged by a white mob in Duluth, Minnesota, in the northern United States.source
July 26 – Anti-semitic paramilitary attacks guests at Club Kávéház, kill 2 peopleHungary source
September 22 – The London Metropolitan Police forms the Flying Squad, a motorised mobile detective patrol unit.source
December – Madge Easton Anderson becomes the first woman admitted to practice as a professional lawyer in the UK when she qualifies as a solicitor (law agent) in Scotland.Scotland source
O Crime de Cravinhos, directed by Arturo Carrari and starring Rodolfo Arena.Brazil source
Identification of Prisoners ActIndia source
Wellington Cup – Kilmoon / Oratress (dead heat)New Zealand source
Helge Løvland, won the Olympic gold medal in the decathlon.Norway source

Disasters & Accidents

9 January – The cargo steamer Treveal is wrecked in the English Channel; 35 people lose their lives.United Kingdom source
May 18 – Minister of the Interior Mihály Dömötör bans freemasonry by decreeHungary source
July 13 – In reaction the 'Split incident', Italian Fascist Blackshirts, led by Francesco Giunta, destroy the Trieste National Hall (Narodni dom), the center of the Slovene theatre in Trieste (another former Austro-Hungarian city under Italian military occupation).Italy source
13 July – London County Council bans aliens from almost all council jobs.United Kingdom source
27 July - Tour de France ends, won by Philippe Thys of Belgium.France source
August–September – Armed metal workers in Milan and Turin occupied their factories in response to a lockout by the employers. Factory occupations swept the "industrial triangle" of north-western Italy. Some 400,000 metal-workers and 100,000 others took part. On September 3, 185 metal-working factories in Turin had been occupied.Italy source
20 September – "Sack of Balbriggan" in County Dublin: Black and Tans destroyed more than fifty properties in the town.Ireland source
3 December - Five crew members from the Rhoscolyn lifeboat are lost off Llanddwyn, Anglesey.Wales source

Climate & Environment

January 3: The 7.8 Ms Veracruz earthquake affected the eastern part of the country with a maximum Mercalli intensity of X–XII. Between 648 and 4,000 were killed and 167 were injured.Mexico source
February 20 – 1920 Gori earthquake: An earthquake hits Gori in the Democratic Republic of Georgia, killing 114.source
May 29 – Floods at Louth, Lincolnshire in England kill 23.source
29 May – Louth flood of 1920 in Lincolnshire kills 23.United Kingdom source
1 June – Adelaide has its wettest June day on record from a vigorous cold front with 53.6 millimetres setting the scene for the wettest winter on record in the Murray–Darling basin and second-wettest for all of southern Australia.Australia source
June 21 – The 4.9 Ml Inglewood earthquake shakes the Los Angeles Area with a maximum Mercalli intensity of VIII (Severe), causing more than $100,000 in damage.United States source
July 11 – Split incident. After a Yugoslav flag is removed by two Italian naval officers in Split, a former Austro-Hungarian city under Italian military occupation, street conflict erupts between Italians and Croats. During a violent confrontation with a group of Croats, the captain and a sailor of Italian cruiser Puglia were shot and killed as well as a Croat civilian.Italy source
19 August – Following his conviction by court martial for sedition, the Lord Mayor of Cork, Terence MacSwiney, went on hunger strike in Brixton Prison in London.Ireland source
September 7 – A magnitude 6.6 earthquake hits Garfagnana and Lunigiana in Tuscany, killing 170 people; families left homeless numbered in the thousands.Italy source
December 16 – An 8.2 Richter scale Haiyuan earthquake causes a landslide in Gansu Province, China, killing 273,000.source
December 16 – 1920 Haiyuan earthquakeChina source

Culture & Society

10 January – The League of Nations is established with Switzerland as one of its founding members and its headquarters established in Geneva.Switzerland source
January 16 – Zeta Phi Beta sorority, is founded on the campus of Howard University in Washington, D.C.source
January 19 – The American Civil Liberties Union (ACLU) is founded.source
February 10 – General Józef Haller first performs Poland's Wedding to the Sea, a symbolic celebration of the restitution of Polish access to the Baltic Sea.source
February 14 – The League of Women Voters is founded in Chicago.source
February 22 – In Emeryville, California, the first dog racing track to employ an imitation rabbit opens.source
March 1 – Hungarian admiral and statesman Miklós Horthy becomes the Regent of Hungary.source
March 29 – Sir William Robertson is promoted to Field Marshal, the first man to rise from private (enlisted 1877) to the highest rank in the British Army.source
20 April - Opening ceremony of the 1920 Summer Olympics in Antwerp, at which Brazil competes for the first time. Sport shooter Guilherme Paraense is the first Brazilian to win a gold medal.Brazil source
May 10 – Agnès Souret is elected "The most beautiful woman in France", retrospectively considered the first Miss France.source
June 28 – Sigma Tau Gamma is founded on campus at the University of Central Missouri in Warrensburg, Missourisource
July 30–August 8 – The 1st World Scout Jamboree is held at Olympia, London.source
August 14–September 12 – Main events of the 1920 Summer Olympics in Antwerp, Belgium (there have been ceremonies and outlying events since April). The Olympic symbols of five interlocking rings and the associated flag are first displayed at the games.source
August 22 – The Salzburg Festival in Austria is inaugurated as a regular event.source
September 5 – Mahatma Gandhi launches the non-cooperation movement in India, with the goal of obtaining independence from British rulesource
September 9 – The Lotta Svärd women's paramilitary auxiliary is founded in Finland.source
September 17 – The National Football League is established, as the American Professional Football Association.source
September 17 – The Victory Medal, a commemorative military medal of Japan awarded to mark service during the First World War, is established by Imperial Edict.Japan source
September 21 – The Communist Party of Uruguay is founded.source
October 3 – The Prix de l'Arc de Triomphe horse race first runs in Paris.source
October 4 – The Mannerheim League for Child Welfare, a Finnish non-governmental organization, is founded on the initiative of Sophie Mannerheim.source
October 20 – Order of Vitéz foundedHungary source
20 October – Over 400,000 workers engage in a general strike that lasts until 28 October.Romania source
October 27 – The League of Nations moves its headquarters to Geneva, Switzerland.source
October 30 – The Communist Party of Australia is founded in Sydney.source
October – English writer Agatha Christie's first novel, The Mysterious Affair at Styles, appears in the U.S., introducing her long-running Belgian detective character Hercule Poirot in the setting of an English country house. (The book is published in the U.K. in 1921.)source
November 14 – The Edmonton Symphony Orchestra holds its first concert, in Alberta.source
November 20 – Prince Arthur of Connaught is appointed the 3rd Governor-General of South Africa.source
November 20 – Prince Arthur of Connaught is appointed the 3rd Governor-General of the Union of South Africa.South Africa source
6 December – The Histadrut is established in Haifa to look after the interests of Jewish workers.British-administered Palestine source
Portugal competes in Fencing and Shooting at the Summer OlympicsPortugal source

Births

January 2 – Isaac Asimov, American author (died 1992)source
January 6 – Sun Myung Moon, Korean evangelist, founder of the Unification Church (died 2012)source
January 22 – Sir Alf Ramsey, English footballer and manager (died 1999)source
February 11 – Farouk I, King of Egypt (died 1965)source
March 17 – Sheikh Mujibur Rahman, founder, 2-time president and second prime minister of Bangladesh (died 1975)source
May 18 – Pope John Paul II (died 2005)source
June 11 – King Mahendra of Nepal (died 1972)source
June 28 – Clarissa Eden, wife of British prime minister Anthony Eden (died 2021)source
July 25 – Rosalind Franklin, British crystallographer (died 1958)source
August 17 – Maureen O'Hara, Irish-American actress (died 2015)source
August 22 – Ray Bradbury, American science fiction writer (died 2012)source
August 29 – Charlie Parker, African-American saxophonist, composer (died 1955)source
September 23 – Mickey Rooney, American actor, dancer and entertainer (died 2014)source
October 22 – Timothy Leary, American psychologist, author and proponent of LSD (died 1996)source
27 October – Ts'ao Yung-ho, Taiwanese historianTaiwan source
5 November – Kató Havas, violinist (died 2018).Romania source
December 12 – Salim Neisari, Iranian writer.Iran source
24 December – Edy Reinalter, alpine skier (died 1962 in Austria)Switzerland source

Deaths

January 7 – Sir Edmund Barton, 1st prime minister of Australia (born 1849)source
February 7 – Alexander Kolchak, Russian naval commander; executed (born 1874)source
12 February – Adolf Frey – writer and historian (born 1855)Switzerland source
February 17 – A woman named Anna Anderson tries to commit suicide in Berlin and is taken to a mental hospital where she claims she is Grand Duchess Anastasia of Russia.source
February 20 – Robert Peary, American Arctic explorer (born 1856)source
27 February – Alexandru Dimitrie Xenopol, historian and philosopher (born 1847).Romania source
1 March – Zionist activist Joseph Trumpeldor and five Palestinian Jewish fighters are killed in the battle of Tel Hai. The battle, which gave Tel Hai its long-enduring fame, was significant far beyond the small number of fighters involved on either side – mainly due to its influence on Zionist history, both inspiring an enduring heroic myth and profoundly influencing Zionist military and political strategies over several decades.British-administered Palestine source
April 4 – 1920 Palestine riots: Violence erupts between Arab and Jewish residents in Jerusalem; 9 are killed, 216 injured.source
April 26 – Srinivasa Ramanujan, Indian mathematician (born 1887)source
May 21 – Venustiano Carranza, President of Mexico (born 1859)source
June 13 – Essad Pasha Toptani, nominal ruler of Albania, is assassinated by Avni Rustemi in Paris.source
June 14 – Max Weber, German political economist (born 1864); Spanish flusource
July 10 – John Fisher, 1st Baron Fisher, British admiral (born 1841)source
July 24 – Battle of Maysalun: The French defeat the Syrian army, whose leader Yusuf al-'Azma is killed. French troops occupy Damascus and depose Faisal I of Syria as king.source
August 31 – Wilhelm Wundt, German physiologist, psychologist (born 1832)source
October 24 – Grand Duchess Maria Alexandrovna of Russia (born 1853)source
December 11 – Burning of Cork in Ireland: British forces set fire to some 5 acres of the centre of Cork, including the City Hall, in reprisal attacks, after a British auxiliary is killed in a guerilla ambush.source
December 14 – Gen. Benjamín Hill, Secretary of War, dies in suspicious circumstances. (born 1877)Mexico source