1920s

Sometimes referred to as the "Roaring Twenties".

Events and trends

Technology

• John T. Thompson invents Thompson submachine gun, also known as "Tommy Gun."
• John Logie Baird invents the first working television system. (1925)
• Charles Lindbergh becomes the first person to fly solo non-stop across the Atlantic Ocean (20 May-21 May 1927)
• Penicillin is discovered by Sir Alexander Fleming. (1928)
• Radio Broadcasting reached a tipping point and began to become feasible in the 1920s, with the widespread introduction of radio receivers
• Insulin is discovered by Frederick Banting during the winter of 1921–1922

Science

• Great advances in quantum mechanics
  • Wave mechanics and the Schrödinger equation
  • Werner Heisenberg formulates the uncertainty principle
  • Paul Dirac's unification of quantum mechanics with special relativity

War, peace and politics

• Rise of communism after World War I
• The Red Scare (1920–1921)
• In the United States, peak of the Ku Klux Klan (about three million members)
• Irish Civil War
• The Irish Free State gains independence from the United Kingdom in 1922
• Turkish War of Independence
• Polish-Soviet war
• First Labour Government of Ramsay MacDonald formed in the United Kingdom
• Kellogg-Briand Pact to end war

Economics

• Economic boom ended by "Black Tuesday" (October 29, 1929); the stock market crashes, leading to the Great Depression

Culture, religion

• Youth culture of The Lost Generation; flappers, Charleston, bobbed hair
• Prohibition — legal attempt to end consumption of alcohol in the USA
• "The Jazz Age" — Jazz and jazz-influenced dance music widely popular
• Rise of broadcast radio as an entertainment medium
• Start of commercially viable "Talking Pictures" (motion pictures with sound tracks)
• Beginning of surrealist movement
• Beginning of the Art Deco movement
• Fads such as dance marathons, mah-jongg, crossword puzzles and pole-sitting are popular
• The Harlem Renaissance
• The Scopes Trial (1925) which questioned evolution

People

World leaders

• Prime Minister William Lyon Mackenzie King (Canada)
• President Sun Yat-sen (Republic of China)
• President Chiang Kai-shek (Republic of China)
• President Paul von Hindenburg (Germany)
• King Victor Emmanuel III (Italy)
• Prime Minister Benito Mussolini (Italy)
• President W.T. Cosgrave (Irish Free State)
• President Mustafa Kemal(Attaturk) (Turkey)
• Emperor Hirohito (Japan)
• Pope Pius XI
• Vladimir Lenin (Soviet Union)
• Joseph Stalin (Soviet Union)
• King George V (United Kingdom)
• Prime Minister David Lloyd George (United Kingdom)
• Prime Minister Andrew Bonar Law (United Kingdom)
• Prime Minister Stanley Baldwin (United Kingdom)
• Prime Minister Ramsay MacDonald (United Kingdom)
• President Woodrow Wilson (United States)
• President Warren G. Harding (United States)
• President Calvin Coolidge (United States)
• President Herbert Hoover (United States)

Entertainers

• Charlie Chaplin
• George Gershwin
• Duke Ellington
• Fletcher Henderson
• Al Jolson
• Jelly Roll Morton
• Cole Porter
• Bessie Smith
• Rudy Vallee
• Paul Whiteman
• Louis Armstrong
• Eddie Cantor
• Helen Kane
• Buster Keaton

Sports figures

• Babe Ruth (U.S. baseball player)
• Gordon Coventry (Australian Australian Rules Football player)
• Bill Tilden (U.S. tennis player)
• Jack Dempsey (U.S. boxer)
• Red Grange (U.S. American football player)
• Bobby Jones (U.S. golfer)