January 3 – Theodoros Pangalos declares himself dictator in Greece
January 8 – Crown Prince Nguyễn Phúc Vĩnh Thuy ascends the throne, the last monarch of Vietnam
January 26 – Scottish inventor John Logie Baird demonstrates a mechanical television system for members of the Royal Institution, and a reporter from The Times, at his London laboratory.
March 6 – The Shakespeare Memorial Theatre in Stratford-upon-Avon is destroyed by fire.
March 14 – The El Virilla train accident occurs in Costa Rica killing 248 and injuring 93.
March 16 – Robert Goddard launches the first liquid-fuel rocket, at Auburn, Massachusetts.
April 17 – Zhang Zuolin’s army captures Beijing
April 21 – Princess Elizabeth Alexandra Mary of York, later Elizabeth II of the United Kingdom, is born in Mayfair, London.
April 25 – Rezā Khan is crowned Shah of Iran, under the name ”Pahlevi”.
May 4 – The United Kingdom general strike begins at midnight, in support of the coal strike.
May 9 – Richard E. Byrd and Floyd Bennett claim to be the first to fly over the North Pole, though their claim is later disputed.
May 12 – Roald Amundsen and his crew fly over the North Pole, in the airship Norge.
May 12–14 – Józef Piłsudski takes over in Poland in the May Coup
May 18 – Evangelist Aimee Semple McPherson disappears, while visiting a Venice, California beach.
June 4 – Ignacy Mościcki becomes president of Poland.
July 10 – A bolt of lightning strikes Picatinny Arsenal in New Jersey; the resulting fire causes several million pounds of explosives to blow up in the next 2–3 days.
August 5 – In New York, the Warner Brothers’ Vitaphone system premieres, with the movie Don Juan, starring John Barrymore.
August 23 – The sudden death of popular film actor and sex symbol Rudolph Valentino, at age 31, causes mass grief and hysteria around the world.
September 1 – Lebanon under the French Mandate gets its first constitution, thereby becoming a republic. Charles Debbas is elected president.
September 11 – In Rome, Italy, Gino Lucetti throws a bomb at Benito Mussolini’s car, but Mussolini is unhurt.
September 18 – A strong hurricane devastates Miami, leaving over 100 dead and causing several hundred million dollars in damage.
September 25 – The League of Nations Slavery Convention abolishes all types of slavery.
October 14 – A. A. Milne’s children’s book Winnie-the-Pooh is published in London, featuring the eponymous bear.
October 23 – Leon Trotsky and Lev Kamenev are removed from the Politburo of the Central Committee of the Communist Party of the Soviet Union.
October 31 – Magician Harry Houdini dies of gangrene and peritonitis that has developed after his appendix ruptured.
November 15 – The Balfour Declaration is approved by the 1926 Imperial Conference, making the Commonwealth dominions equal and independent.
December 2 – British prime minister Stanley Baldwin ends the martial law that had been declared, due to the general strike.
December 3 – Agatha Christie disappears from her home in Surrey; on December 14 she is found at a Harrogate hotel.
December 17 – A democratically elected government is overthrown in Lithuania. Antanas Smetona assumes power.
December 26 – The Japanese Shōwa period begins from this day, due to the death of Emperor Taishō on the day before. His son Hirohito will reign as Emperor until 1989.