January 1 – The British Broadcasting Company becomes the British Broadcasting Corporation. John Reith becomes the first Director-General
January 1 – The Cristero War erupts in Mexico when Catholic rebels attack the government, which had placed heavy restrictions on the church.
January 9 – A fire at the Laurier Palace movie theatre in Montreal, Quebec, Canada, kills 78 children
January 11 – Louis B. Mayer, head of film studio Metro-Goldwyn-Mayer (MGM), announces the creation of the Academy of Motion Picture Arts and Sciences, at a banquet in Los Angeles, California
January 24 – U.S. Marines invade Nicaragua by orders of President Calvin Coolidge, intervening in the Nicaraguan Civil War, and remaining in the country until 1933.
February – Werner Heisenberg formulates his famous uncertainty principle, while employed as a lecturer at Niels Bohr’s Institute for Theoretical Physics, at the University of Copenhagen.
February 23 – The U.S. Federal Radio Commission begins to regulate the use of radio frequencies.
March 7 – A 7.0 Mw earthquake kills at least 2,925 in the Toyooka and Mineyama areas of western Honshu, Japan.
March 11 – In New York City, the Roxy Theatre is opened by Samuel Roxy Rothafel.
March 24 – After six foreigners have been killed in Nanking, warships of the U.S. Navy and the British Royal Navy fire shells and shot to disperse the crowds.
March 29 – Henry Segrave breaks the land speed record, driving the Sunbeam 1000 hp at Daytona Beach, Florida.
April 7 – Bell Telephone Co. transmits an image of Herbert Hoover (then the Secretary of Commerce), which becomes the first successful long distance demonstration of television.
April 22–May 5 – The Great Mississippi Flood of 1927 strikes 700,000 people, in the greatest natural disaster in American history through this time.
April 27 – João Ribeiro de Barros becomes the first non-European to make a transatlantic flight, flying from Genoa, Italy, to Fernando de Noronha, Brazil.
May 18 – A series of violent attacks results in 45 deaths, mostly of school children, in Bath Township, Michigan.
May 20 – By the Treaty of Jeddah, the United Kingdom recognizes the sovereignty of Ibn Saud over the Kingdom of Hejaz and Nejd, the future Saudi Arabia.
May 20–21– Charles Lindbergh makes the first solo, nonstop transatlantic airplane flight, from New York City to Paris, France, in his single-engined aircraft, the Spirit of St. Louis.
May 22 – The 7.6 Mw Gulang earthquake affects Gansu in northwest China with a maximum Mercalli intensity of XI (Extreme), leaving over 40,000 dead.
July 15 – After police in Vienna fire on an angry crowd, 85 protesters (mostly members of the Social Democratic Party of Austria) and 5 policemen are left dead, and more than 600 are injured.
August 1 – The Communist Chinese People’s Liberation Army is formed, during the Nanchang Uprising.
August 2 – U.S. President Calvin Coolidge announces, ”I do not choose to run for president in 1928.”
August 10 – The Mount Rushmore Park is rededicated in the United States. President Calvin Coolidge promises national funding for the proposed carving of the presidential figures.
August 22 – Protests are held around the world against the death sentences on Italian American anarchists Sacco and Vanzetti.They are executed the next day.
September – The Autumn Harvest Uprising occurs in China.
October 8 – The ”Murderers’ Row” team of the New York Yankees complete a four-game sweep of the Pittsburgh Pirates in the World Series.
October 27 – Worthington, Ohio, collapses into a lake due to mine shafts underground – as the town has already been evacuated, there are no injuries
November 12 – Leon Trotsky is expelled from the Soviet Communist Party, leaving Joseph Stalin with undisputed control of the Soviet Union
December 1 – Chiang Kai-shek marries Soong Mei-ling in Shanghai.
December 14 – Iraq gains independence from the United Kingdom.
December 27 – Kern and Hammerstein’s musical play, Show Boat, based on Edna Ferber’s novel, opens on Broadway and then goes on to become the first great classic of the American musical theater.
December 30 – The first Asian commuter metro line, the Tokyo Metro Ginza Line, opens in Japan.