1927 1928 1929 - 1930 - 1931 1932 1933
1900s 1910s 1920s - 1930s - 1940s 1950s 1960s
- January 6
- The first diesel engine automobile trip is completed (Indianapolis, Indiana, to New York City).
- January 26 – The Indian National Congress declares 26 January as Independence Day or as the day for Poorna Swaraj (Complete Independence).
- January 30 – The first radiosonde is launched in Pavlovsk, USSR.
- January 31 – The 3M company markets Scotch Tape.
- February 18 – While studying photographs taken in January, Clyde Tombaugh discovers Pluto, a heavenly body considered a planet until 2006, when the term "planet" was officially defined. Pluto is now considered a Dwarf Planet.
- March 2 – Mahatma Gandhi informs the British viceroy of India that civil disobedience will begin 9 days later.
- March 6 – The first frozen foods of Clarence Birdseye go on sale in Springfield, Massachusetts.
- March 12 – Mahatma Gandhi sets off on a 200-mile protest march towards the sea with 78 followers to protest the British monopoly on salt; more will join them during the Salt March that ends on April 5.
- March 28 – Constantinople and Angora change their names to Istanbul and Ankara.
- March 29 – Heinrich Brüning is appointed German Reichskanzler.
- March 31 – The Motion Pictures Production Code is instituted, imposing strict guidelines on the treatment of sex, crime, religion and violence in motion pictures for the next 40 years.
- April 4 – The Communist Party of Panama is founded.
- April 5 – In an act of civil disobedience, Mahatma Gandhi breaks British law after marching to the sea and making salt.
- April 18 – The Chittagong Rebellion begins in India.
- April 21
- April 22 – The United Kingdom, Japan and the United States sign the London Naval Treaty regulating submarine warfare and limiting shipbuilding.
- May 4/May 5 – Mahatma Gandhi is arrested again.
- May 6 – The Great Salmas Earthquake in Iran (7.3 on the Richter Scale) kills 4,000 people.
- May 10 – The National Pan-Hellenic Council is founded in Washington, D.C..
- May 16 – Rafael Leónidas Trujillo is elected president of the Dominican Republic.
- May 17 – French Prime Minister André Tardieu decides to withdraw the remaining French troops from the Rhineland (they depart by June 30).
- May 20 – Sergei Eisenstein arrives in New York City.
- May 24 – Amy Johnson lands in Darwin, Australia, becoming the first woman to fly solo from England to Australia (she left on May 5 for the 11,000 mile flight).
- May 30
- June 9 – Chicago Tribune journalist Jake Lingle is shot in Chicago, Illinois. Newspapers promise $55,000 reward for information. Lingle is later found to have had contacts with organized crime.
- June 17 – U.S. President Herbert Hoover signs the Smoot-Hawley Tariff Act into law.
- June 21 – One-year conscription comes into force in France.
- July 5 – The Seventh Lambeth Conference of Anglican Christian bishops opens. This conference approved the use of artificial birth control in limited circumstances, marking a controversial turning point in Christian views on contraception.
- July 7
- July 28 – Richard Bennett defeats William Lyon Mackenzie King in federal elections and becomes the Prime Minister of Canada.
- August 7 – Richard Bennett becomes Canada's eleventh prime minister.
- August 12 – Turkish troops move into Persia to fight Kurdish insurgents.
- August 27 – A military junta takes over in Peru.
- September 6 – José Félix Uriburu carries out a successful military coup, overthrowing Hipólito Yrigoyen, President of Argentina.
- September 14 – National Socialists win 107 seats in the German Parliament (18.3% of all the votes), making them the second largest party.
- September 20 – The Eastern Catholic Rite Syro-Malankara Catholic Church is formed.
- October 5 – British Airship R101 crashes in France en-route to India on its maiden voyage.
- October 24 – Revolution of 1930: Getúlio Dornelles Vargas takes power in Brazil.
- November 2 – Haile Selassie is crowned emperor of Ethiopia.
- November 3 – Getúlio Vargas becomes president of Brazil.
- November 25 – An earthquake in the Izu Peninsula of Japan kills 223 people and destroys 650 buildings.
- December – Turkish women are given the right to vote.
- December 2 – Great Depression: U.S. President Herbert Hoover goes before Congress and asks for a US$150 million public works program to help generate jobs and stimulate the economy.
- December 19 – Merapi volcano in Indonesia erupts, killing 1,300.
- December 24 – In London, Harry Grindell Matthews demonstrates his device to project pictures to the clouds.
- December 28 – Mohandas Gandhi leaves for Britain for negotiations.
- December 29 – Sir Muhammad Iqbal's presidential address in Allahabad introduces the Two-Nation Theory, outlining a vision for the creation of Pakistan.
- February 18 - Bradley R. Smith, free speech activist and historical revisionist (d. 2016)
- April 3 - Helmut Kohl, Chancellor of Germany
- April 11 - Anton LaVey, Jewish founder of the Church of Satan (d. 1997)
- August 5 - Neil Armstrong, American astronaut and first man on the Moon. (d. 2012)
- October 6 - Hafez al-Assad, President of Syria (d. 2000)