January
January 1
Flooding in the Rhine River strikes Cologne.
Ireland's first regular radio service, 2RN (later Radio Éireann), begins broadcasting.
Turkey switches to the Gregorian calendar after reforms set by Kemal Atatürk.
January 3 – Theodoros Pangalos declares himself dictator in Greece.
January 8 – Abdul-Aziz ibn Saud is crowned King of Hejaz.
January 12 – Freeman Gosden and Charles Correll premiere their radio program Sam 'n' Henry, in which the two white performers portray two black characters from Harlem looking to strike it rich in the big city. It is a precursor to Gosden and Correll's more popular later program, Amos 'n' Andy.
January 16 – A BBC radio play about a workers' revolution causes a panic in London.
January 21 – The Belgian Parliament accepts the Locarno Treaties.
January 26 – John Logie Baird demonstrates a mechanical television system.
January 29 – Eugene O'Neill's The Great God Brown opens at the Greenwich Theatre.
January 31 – British and Belgian troops leave Cologne.
February
February 1 – Land on Broadway and Wall Street in New York City is sold at a record $7 per sq inch.
February 8 – Seán O'Casey's The Plough and the Stars opens at the Abbey Theatre in Dublin.
February 9 – Flooding hits London suburbs.
February 12 – The Irish minister for Justice, Kevin O'Higgins, appoints the Committee on Evil Literature.
February 20 – The Berlin International Green Week debuts in Berlin.
February 25 – Francisco Franco becomes General of Spain.
March
March 16: Goddard with rocket in 1926.
March 6 – The Shakespeare Memorial Theatre in Stratford-upon-Avon is destroyed by fire.
March 16 – Robert Goddard launches the first liquid-fuel rocket, at Auburn, Massachusetts.
March 23 – Éamon de Valera organizes Fianna Fáil in Ireland.
April
April 4 – Greek dictator Theodoros Pangalos is elected president.
April 7 – An assassination attempt against Italian Fascist leader Benito Mussolini fails.
April 12 – By a vote of 45–41, the United States Senate unseats Iowa Senator Smith W. Brookhart and seats Daniel F. Steck, after Brookhart had already served for over one year.
April 16 – A train crash in San José, Costa Rica kills 178 people.
April 24 – Treaty of Berlin: Germany and the Soviet Union each pledge neutrality in the event of an attack on the other by a third party for the next five years.
April 25 – Rezā Khan is crowned Shah of Iran under the name "Pahlevi".
April 30 – African-American pilot Bessie Coleman is killed after falling 500 feet (150 m) from an airplane.
May
May 3 – Coal miners are locked-out in Britain.
May 4 – The United Kingdom general strike begins at midnight in support of the coal strike.
May 9
Martial law is declared in Britain because of the general strike.
The French navy bombards Damascus because of the Druze riots.
Admiral Richard E. Byrd and Floyd Bennett claim to have flown over the North Pole in a monoplane (later discovery of his diary seems to indicate that this did not happen).
May 10
Talks between the government and strikers begin in the U.K.
Planes piloted by Major Harold Geiger and Horace Meek Hickam, students at the Air Corps Tactical School, collide in mid-air at Langley Field, Virginia. Hickam parachutes to safety.
May 12
Roald Amundsen flies over the North Pole in the airship Norge.
UK General Strike 1926: In the United Kingdom, a general strike by trade unions ends (the strike began on May 3).
May 12–May 14 – May Coup: Józef Piłsudski takes over in Poland.
May 18 – Evangelist Aimee Semple McPherson disappears while visiting a Venice, California beach.
May 20 – The United States Congress passes the Air Commerce Act, licensing pilots and planes.
May 23 – The first Lebanese constitution is established.
May 26 – The Rifkabyl rebels surrender in Morocco.
May 28 – The 1926 coup d'état commanded by Manuel Gomes da Costa in Portugal installs the Ditadura Nacional (National Dictatorship), followed by António de Oliveira Salazar's Estado Novo.
June
June 4 – Ignacy Mościcki becomes president of Poland.
June 19 – DeFord Bailey is the first African-American to perform on Nashville's Grand Ole Opry.
June 29 – Arthur Meighen returns to office as Prime Minister of Canada.
July
July 1 – The Kuomintang begins a military unification campaign in northern China.
July 3 – A Caudron C.61 aircraft operated by Compagnie Internationale de Navigation Aérienne crashes in Czechoslovakia.
July 9 – General Óscar Carmona takes power in a military coup in Portugal.
July 12 – A lightning strike destroys an ammunition depot in Dover, New Jersey.
July 15 – BEST buses make their début in Bombay.
July 23 – Fox Film buys the patents of the Movietone sound system for recording sound onto film.
July 26 – The National Bar Association incorporates in the United States.
August
August 1 – In Mexico, the entry into force of anticlerical measures stipulated in the constitution of 1917 causes the Cristero War.
August 6
Gertrude Ederle becomes the first woman to swim the English Channel from France to England.
In New York, the Warner Brothers' Vitaphone system premieres with the movie Don Juan starring John Barrymore.
August 18
The British miners' union begins negotiations with the government.
A weather map is televised for the first time, sent from NAA Arlington to the Weather Bureau office in Washington, D.C.
August 22 – In Greece, Georgios Kondylis ousts Theodoros Pangalos.
August 23 – The sudden death of popular Hollywood actor and sex symbol Rudolph Valentino at the age of only 31 years old causes mass grief and hysteria around the world.
August 25 – Pavlos Kountouriotis announces that dictatorship has ended in Greece and becomes the president.
September
September 1 – Lebanon under the French Mandate gets its first constitution, thereby becoming a republic. Charles Debbas is elected president.
September 8 – The German Weimar Republic joins the League of Nations.
September 11
Aloha Tower is officially dedicated at Honolulu Harbor in the Territory of Hawai'i.
In Rome, Italy, Gino Lucetti throws a bomb against Benito Mussolini's car.
September 14 – The Locarno Treaties of 1925 are ratified in Geneva and come into effect.
September 16 – Philip Dunning and George Abbott's play Broadway premieres in New York City.
September 18 – Great Miami Hurricane: A strong hurricane devastates Miami, leaving over 100 dead and causing several hundred million dollars in damage (equal to nearly $100 billion today).
September 20 – Twelve blue cars full of gangsters open fire at the Hawthorne Inn, Al Capone's Chicago headquarters. Only one of Capone's men is wounded.
September 21 – French war ace René Fonck and three others attempt to fly the Atlantic in pursuit of the Orteig Prize. Before the newsreel cameras at Roosevelt Field New York, the modified Sikorsky S-35 crashes on take-off and bursts into flames. Fonck survives but two of his men are killed.
September 23 – Gene Tunney defeats Jack Dempsey and becomes heavyweight champion of the world.
September 25
The League of Nations Slavery Convention abolishes all types of slavery.
William Lyon Mackenzie King returns to office as Prime Minister of Canada.
October
October 2 – Józef Piłsudski becomes prime minister of Poland.
October 12 – British miners agree to end their strike.
October 14 – A. A. Milne's children's book Winnie-the-Pooh is published in London, featuring the eponymous bear.
October 19 – The 1926 Imperial Conference opens in London.
October 20 – A hurricane kills 650 in Cuba. The same hurricane also sinks the Black Duck a famous rum-running vessel under the command of Jack Recker (Savannah Unknown)
October 23
Leon Trotsky and Lev Kamenev are removed from the Politburo of the Central Committee of the Communist Party of the Soviet Union.
A decree in Italy bans women from holding public office.
The Fazal Mosque, the first purpose-built in London and the first Ahmadiyya mosque in Britain, is completed.
October 31 – Magician Harry Houdini dies of gangrene and peritonitis that has developed after his appendix ruptured.
November
November 5 – The APOEL FC is founded.
November 10 – In San Francisco, a necrophiliac serial killer named Earle Nelson (dubbed "Gorilla Man") kills and then rapes his 9th victim, a boarding house landlady named Mrs. William Edmonds.
November 11 – U.S. Route 66 is established.
November 15
The NBC radio network opens with 24 stations (formed by Westinghouse, General Electric and RCA).
The Balfour Declaration is approved by the 1926 Imperial Conference, making the Commonwealth dominions equal and independent.
November 24
The village of Rocquebillier in the French Riviera is almost destroyed in a massive hailstorm.
Sri Aurobindo retires, leaving The Mother to run the Sri Aurobindo Ashram in Puducherry, India.
November 25 – The death penalty is re-established in Italy.
November 26 – All Italian Communist deputies are arrested.
November 27 – The restoration of Colonial Williamsburg begins in Williamsburg, Virginia.
December
December 2 – British prime minister Stanley Baldwin ends the martial law that had been declared due to general strike.
December 3 – Agatha Christie disappears from her home in Surrey; on December 14 she is found at a Harrogate hotel.
December 7 – The Council for the Preservation of Rural England (CPRE) founded; now the Campaign to Protect Rural England.
December 17 – 1926 Lithuanian coup d'état: A democratically elected government is overthrown in Lithuania; Antanas Smetona assumes power.
December 18 – Turkey converts to the Gregorian calendar, making the next day January 1 1927.
December 26 – In the history of Japan, the Shōwa period begins from this day due to the death of Emperor Taishō on the day before. His son Hirohito will reign as Emperor of Japan until 1989.
January 1
Flooding in the Rhine River strikes Cologne.
Ireland's first regular radio service, 2RN (later Radio Éireann), begins broadcasting.
Turkey switches to the Gregorian calendar after reforms set by Kemal Atatürk.
January 3 – Theodoros Pangalos declares himself dictator in Greece.
January 8 – Abdul-Aziz ibn Saud is crowned King of Hejaz.
January 12 – Freeman Gosden and Charles Correll premiere their radio program Sam 'n' Henry, in which the two white performers portray two black characters from Harlem looking to strike it rich in the big city. It is a precursor to Gosden and Correll's more popular later program, Amos 'n' Andy.
January 16 – A BBC radio play about a workers' revolution causes a panic in London.
January 21 – The Belgian Parliament accepts the Locarno Treaties.
January 26 – John Logie Baird demonstrates a mechanical television system.
January 29 – Eugene O'Neill's The Great God Brown opens at the Greenwich Theatre.
January 31 – British and Belgian troops leave Cologne.
February
February 1 – Land on Broadway and Wall Street in New York City is sold at a record $7 per sq inch.
February 8 – Seán O'Casey's The Plough and the Stars opens at the Abbey Theatre in Dublin.
February 9 – Flooding hits London suburbs.
February 12 – The Irish minister for Justice, Kevin O'Higgins, appoints the Committee on Evil Literature.
February 20 – The Berlin International Green Week debuts in Berlin.
February 25 – Francisco Franco becomes General of Spain.
March
March 16: Goddard with rocket in 1926.
March 6 – The Shakespeare Memorial Theatre in Stratford-upon-Avon is destroyed by fire.
March 16 – Robert Goddard launches the first liquid-fuel rocket, at Auburn, Massachusetts.
March 23 – Éamon de Valera organizes Fianna Fáil in Ireland.
April
April 4 – Greek dictator Theodoros Pangalos is elected president.
April 7 – An assassination attempt against Italian Fascist leader Benito Mussolini fails.
April 12 – By a vote of 45–41, the United States Senate unseats Iowa Senator Smith W. Brookhart and seats Daniel F. Steck, after Brookhart had already served for over one year.
April 16 – A train crash in San José, Costa Rica kills 178 people.
April 24 – Treaty of Berlin: Germany and the Soviet Union each pledge neutrality in the event of an attack on the other by a third party for the next five years.
April 25 – Rezā Khan is crowned Shah of Iran under the name "Pahlevi".
April 30 – African-American pilot Bessie Coleman is killed after falling 500 feet (150 m) from an airplane.
May
May 3 – Coal miners are locked-out in Britain.
May 4 – The United Kingdom general strike begins at midnight in support of the coal strike.
May 9
Martial law is declared in Britain because of the general strike.
The French navy bombards Damascus because of the Druze riots.
Admiral Richard E. Byrd and Floyd Bennett claim to have flown over the North Pole in a monoplane (later discovery of his diary seems to indicate that this did not happen).
May 10
Talks between the government and strikers begin in the U.K.
Planes piloted by Major Harold Geiger and Horace Meek Hickam, students at the Air Corps Tactical School, collide in mid-air at Langley Field, Virginia. Hickam parachutes to safety.
May 12
Roald Amundsen flies over the North Pole in the airship Norge.
UK General Strike 1926: In the United Kingdom, a general strike by trade unions ends (the strike began on May 3).
May 12–May 14 – May Coup: Józef Piłsudski takes over in Poland.
May 18 – Evangelist Aimee Semple McPherson disappears while visiting a Venice, California beach.
May 20 – The United States Congress passes the Air Commerce Act, licensing pilots and planes.
May 23 – The first Lebanese constitution is established.
May 26 – The Rifkabyl rebels surrender in Morocco.
May 28 – The 1926 coup d'état commanded by Manuel Gomes da Costa in Portugal installs the Ditadura Nacional (National Dictatorship), followed by António de Oliveira Salazar's Estado Novo.
June
June 4 – Ignacy Mościcki becomes president of Poland.
June 19 – DeFord Bailey is the first African-American to perform on Nashville's Grand Ole Opry.
June 29 – Arthur Meighen returns to office as Prime Minister of Canada.
July
July 1 – The Kuomintang begins a military unification campaign in northern China.
July 3 – A Caudron C.61 aircraft operated by Compagnie Internationale de Navigation Aérienne crashes in Czechoslovakia.
July 9 – General Óscar Carmona takes power in a military coup in Portugal.
July 12 – A lightning strike destroys an ammunition depot in Dover, New Jersey.
July 15 – BEST buses make their début in Bombay.
July 23 – Fox Film buys the patents of the Movietone sound system for recording sound onto film.
July 26 – The National Bar Association incorporates in the United States.
August
August 1 – In Mexico, the entry into force of anticlerical measures stipulated in the constitution of 1917 causes the Cristero War.
August 6
Gertrude Ederle becomes the first woman to swim the English Channel from France to England.
In New York, the Warner Brothers' Vitaphone system premieres with the movie Don Juan starring John Barrymore.
August 18
The British miners' union begins negotiations with the government.
A weather map is televised for the first time, sent from NAA Arlington to the Weather Bureau office in Washington, D.C.
August 22 – In Greece, Georgios Kondylis ousts Theodoros Pangalos.
August 23 – The sudden death of popular Hollywood actor and sex symbol Rudolph Valentino at the age of only 31 years old causes mass grief and hysteria around the world.
August 25 – Pavlos Kountouriotis announces that dictatorship has ended in Greece and becomes the president.
September
September 1 – Lebanon under the French Mandate gets its first constitution, thereby becoming a republic. Charles Debbas is elected president.
September 8 – The German Weimar Republic joins the League of Nations.
September 11
Aloha Tower is officially dedicated at Honolulu Harbor in the Territory of Hawai'i.
In Rome, Italy, Gino Lucetti throws a bomb against Benito Mussolini's car.
September 14 – The Locarno Treaties of 1925 are ratified in Geneva and come into effect.
September 16 – Philip Dunning and George Abbott's play Broadway premieres in New York City.
September 18 – Great Miami Hurricane: A strong hurricane devastates Miami, leaving over 100 dead and causing several hundred million dollars in damage (equal to nearly $100 billion today).
September 20 – Twelve blue cars full of gangsters open fire at the Hawthorne Inn, Al Capone's Chicago headquarters. Only one of Capone's men is wounded.
September 21 – French war ace René Fonck and three others attempt to fly the Atlantic in pursuit of the Orteig Prize. Before the newsreel cameras at Roosevelt Field New York, the modified Sikorsky S-35 crashes on take-off and bursts into flames. Fonck survives but two of his men are killed.
September 23 – Gene Tunney defeats Jack Dempsey and becomes heavyweight champion of the world.
September 25
The League of Nations Slavery Convention abolishes all types of slavery.
William Lyon Mackenzie King returns to office as Prime Minister of Canada.
October
October 2 – Józef Piłsudski becomes prime minister of Poland.
October 12 – British miners agree to end their strike.
October 14 – A. A. Milne's children's book Winnie-the-Pooh is published in London, featuring the eponymous bear.
October 19 – The 1926 Imperial Conference opens in London.
October 20 – A hurricane kills 650 in Cuba. The same hurricane also sinks the Black Duck a famous rum-running vessel under the command of Jack Recker (Savannah Unknown)
October 23
Leon Trotsky and Lev Kamenev are removed from the Politburo of the Central Committee of the Communist Party of the Soviet Union.
A decree in Italy bans women from holding public office.
The Fazal Mosque, the first purpose-built in London and the first Ahmadiyya mosque in Britain, is completed.
October 31 – Magician Harry Houdini dies of gangrene and peritonitis that has developed after his appendix ruptured.
November
November 5 – The APOEL FC is founded.
November 10 – In San Francisco, a necrophiliac serial killer named Earle Nelson (dubbed "Gorilla Man") kills and then rapes his 9th victim, a boarding house landlady named Mrs. William Edmonds.
November 11 – U.S. Route 66 is established.
November 15
The NBC radio network opens with 24 stations (formed by Westinghouse, General Electric and RCA).
The Balfour Declaration is approved by the 1926 Imperial Conference, making the Commonwealth dominions equal and independent.
November 24
The village of Rocquebillier in the French Riviera is almost destroyed in a massive hailstorm.
Sri Aurobindo retires, leaving The Mother to run the Sri Aurobindo Ashram in Puducherry, India.
November 25 – The death penalty is re-established in Italy.
November 26 – All Italian Communist deputies are arrested.
November 27 – The restoration of Colonial Williamsburg begins in Williamsburg, Virginia.
December
December 2 – British prime minister Stanley Baldwin ends the martial law that had been declared due to general strike.
December 3 – Agatha Christie disappears from her home in Surrey; on December 14 she is found at a Harrogate hotel.
December 7 – The Council for the Preservation of Rural England (CPRE) founded; now the Campaign to Protect Rural England.
December 17 – 1926 Lithuanian coup d'état: A democratically elected government is overthrown in Lithuania; Antanas Smetona assumes power.
December 18 – Turkey converts to the Gregorian calendar, making the next day January 1 1927.
December 26 – In the history of Japan, the Shōwa period begins from this day due to the death of Emperor Taishō on the day before. His son Hirohito will reign as Emperor of Japan until 1989.