1939

1845–1958	Germany [earth sciences]	German naturalist and explorer Alexander von Humboldt lays the basis of modern geography with the publication of Kosmos/Cosmos, in which he arranges geographic knowledge in a systematic fashion.
c. 1931–c. 1940	[aircraft]	Aeroplanes undergo radical changes; they become streamlined, are made almost entirely of metal, acquire controllable-pitch propellers, have air-cooled engines and retractable landing gear, and passengers and crew are protected in soundproofed and insulated cabins.
c. 1931–c. 1940	[technology]	The development of facsimile machines is made possible with the discovery of a dry chemical copying process.
1937–1939	USA [computing]	US mathematician and physicist John V Atanasoff invents an electromechanical digital computer for solving systems of linear equations. It uses punched cards and is the first electronic calculator using electronic vacuum tubes.
1939	USA [everyday life]	For the first time Thanksgiving Day is celebrated on the fourth rather than the last Thursday in November in the USA, in order to guarantee a longer Christmas shopping period.
1939	USA [music]	Americans buy 45 million ‘popular’ music records and 5 million ‘classical’ records.
1939	Germany, Poland, Czechoslovakia [newspapers]	After the German annexation of Czechoslovakia and the invasion of Poland, the free press is closed down in both countries.
1939	USA [photography]	Eastman Kodak in Rochester, New York, produces the first camera with synchronized flash for amateur use.
1939	Germany [physics]	German physicists Hans Bethe and Carl von Weizsäcker propose that nuclear fusion of hydrogen is the source of a star's energy.
1939	France [physics]	The French physicists Frédéric Joliot and Irène Curie-Joliot demonstrate the possibility of a chain reaction when they split uranium nuclei.
1939	USA [radio]	The Radio Corporation of America (RCA) develops the first experimental television sets in the USA.
1939	world, USA [cinema and film]	There are 2,012 films produced worldwide; 483 of these are produced in the USA.
1939	USA [cinema and film]	The film Gone With the Wind, directed by Victor Fleming (with George Cukor and Sam Wood), is released in the USA, premiering in Atlanta, Georgia. Based on the novel by Margaret Mitchell, it stars Vivien Leigh and Clark Gable. One of the most commercially successful films of all time, it runs for 222 minutes and wins eight Academy Awards.
1939	Germany, USA [cinema and film]	The film The Hunchback of Notre Dame, directed by the German film-maker William Dieterle, is released in the USA. Based on the novel by Victor Hugo, it stars Charles Laughton, Cedric Hardwicke, and Maureen O'Hara.
1939	USA [cinema and film]	The classic Western Stagecoach, directed by John Ford, is released in the USA, starring John Wayne, Claire Trevor, Thomas Mitchell, and George Bancroft. Also Ford's film Young Mr Lincoln, starring Henry Fonda is released in the USA.
1939	USA [cinema and film]	The film musical The Wizard of Oz, directed by Victor Fleming and King Vidor, is released in the USA. Based on the novel by Frank L Baum, it stars Judy Garland, Frank Morgan, Ray Bolger, Jack Haley, Bert Lahr, and Margaret Hamilton.
1939	USA [communications]	The US inventor Edwin Armstrong constructs the first FM radio transmitter station.
1939	USA [clothing and fashion]	Warner Brothers' designer Leona Gross Lax in the USA develops the concept of bra cup-sizing.
1939	Ireland [fiction]	The Irish writer James Joyce publishes the final version of his novel Finnegan's Wake (parts had appeared as early as 1928).
1939	USA [fiction]	The US writer John Steinbeck publishes his novel The Grapes of Wrath, a vivid account of the Depression in California.
1939	England [fiction]	The English writer Rumer Godden publishes her novel Black Narcissus. A melodrama set in a convent in the Himalayas, it becomes a best-seller.
1939	USA [food and drink]	The first pre-cooked frozen meals are marketed by General Foods in the USA under the Birds Eye label.
1939	UK [World War II (1939–45)]	The evacuation of around 650,000 children from London to rural England begins. Some 1.5 million people in total will move to the country for part of the war.
1939	Philippines [women's rights]	Women gain the right to vote in the Philippines.
21 January 1939	Germany [administration]	The German Führer dismisses Hjalmar Schacht as president of the Reichsbank for opposing his rearmament expenditure. He replaces him with Walther Funk, minister of economics.
26 January 1939	Spain [Spanish Civil War (1936–39)]	Nationalist forces, assisted by Italian troops, take the city of Barcelona, the last major stronghold of the Republican government in northeastern Spain.
28 January 1939	Ireland [births and deaths]	W B Yeats, Irish poet, dramatist, and nationalist, dies in Roquebrune-Cap-Martin, France (73).
February 1939	UK [everyday life]	The British government begins to build air-raid shelters in areas likely to be bombed in wartime.
2 March 1939	VATICAN [Catholicism]	Following the death of Pope Pius XI on 10 February, Eugenio Pacelli is elected pope and takes the name Pius XII.
15 March 1939	Germany, Czechoslovakia [political events]	German troops occupy Bohemia and Moravia in Czechoslovakia. The German Führer makes a triumphal entry into Prague, the Czech capital, the same evening. The regions become a German protectorate under Konstantin von Neurath.
28 March - 29 March 1939	Spain [Spanish Civil War (1936–39)]	Madrid surrenders to the Spanish Nationalists, after a siege of almost two and a half years. The remaining Republican areas capitulate on 29 March, ending the Spanish Civil War.
31 March 1939	UK, France, Poland [diplomacy]	Britain and France pledge to support Poland in any attack on Polish independence. On 6 April a pact is signed by all three governments confirming the pledge.
April 1939	USA [technology]	US physicists Georges Stibitz and Samuel B Williams of Bell Laboratories build a computer consisting of over 400 relays connected to teletype machine for input and output of data, thus introducing the idea of operating a computer via a terminal. Called a Complex Number Calculator, it is demonstrated on 8 January 1940.
7 April 1939	Italy, Albania [political events]	Italy invades and occupies Albania. The Albanian king, Ahmed Bey Zogu, flees to Greece.
30 April 1939	USA [television]	The National Broadcasting Corporation (NBC) makes the first public demonstration of television in the USA with President Roosevelt opening the New York World's Fair. The broadcast is seen by 1,000 people. Later in the year, NBC begins broadcasting for two hours a week. The Columbia Broadcasting System (CBS) also starts to broadcast.
2 May 1939	USA [baseball]	US baseball player Lou Gehrig withdraws from the lineup after making 2,130 consecutive appearances for the New York Yankees, a sequence that stands as a major league record until 1995.
10 May 1939	USA [Protestantism]	The Methodist Church is reunited after 109 years of division, a split caused between churches in the North and South over slavery.
16 May 1939	USA [food and drink]	Rochester, New York, begins a food-stamp plan to distribute surplus food to the poor, a plan copied by more than 100 US cities in the next two years.
22 May 1939	Germany, Italy [treaties]	The German Führer and Italian prime minister sign a ten-year political and military alliance, the ‘Pact of Steel’.
23 August 1939	USSR, Germany, Poland, Finland, Lithuania, Latvia, Estonia, Romania [treaties]	The USSR and Germany sign a nonaggression agreement. Secret protocols provide for the partition of Poland and for the USSR to operate freely in the Baltic states, Finland, and the Romanian province of Bessarabia.
26 August 1939	USA [television]	The world's first regular advertisements on television are read live by the commentator in the interval of a baseball game in the USA.
27 August 1939	Germany [aircraft]	The Heinkel He 178 makes a test flight in Germany, achieving a speed of 500 kph/360 mph; it is the first jet aeroplane to fly.
1 September 1939	UK [television]	The British Broadcasting Corporation (BBC) stops television broadcasting in the UK for the duration of the war in the middle of a Mickey Mouse film. Service is resumed in 1946.
1 September 1939	Germany, Poland, Italy [World War II (1939–45)]	Germany invades Poland and annexes the free city of Danzig (now Gdansk). Italy declares its neutrality.
3 September 1939	UK, France, Germany, Poland, Australia, New Zealand [World War II (1939–45)]	Britain and France declare war on Germany when it fails to respond to ultimatums following the German invasion of Poland. Australia and New Zealand also declare war on Germany.
3 September 1939	UK [everyday life]	The Citizens' Advice Bureaux scheme is launched in the UK with the opening of 200 offices.
14 September 1939	China, Japan [Sino–Japanese War (1933–40)]	Japanese troops advance south towards the Chinese port of Changsha, but are repulsed. This ends Japanese expansion in central China until 1944.
14 September 1939	USA [aircraft]	The first effective helicopter, the VS-300, designed by Ukranian-born US engineer Igor Sikorsky, makes its first test flight.
17 September 1939	USSR, Poland [World War II (1939–45)]	Red Army troops from the USSR invade Poland from the east, to effect the secretly agreed partition of Poland with Germany.
23 September 1939	Austria [births and deaths]	Sigmund Freud, Austrian neurologist, founder of psychoanalysis, dies in London, England (83).
10 October 1939	USSR, Lithuania [diplomacy]	The USSR signs a pact with Lithuania allowing Soviet troops to be stationed on Lithuanian territory (and in effect reducing the Baltic state to a Soviet colony). The city of Vilna (now Vilnius), formerly in Poland but taken by the USSR on 28 September, is returned to Lithuania.
4 November 1939	USA, UK, France [legislation]	US president Franklin D Roosevelt signs a bill enabling belligerents in the war in Europe to buy arms in the USA on a ‘cash and carry’ basis, provided that such arms are carried in their own ships. Britain's naval blockade of German trade ensures that only Britain and France are able to take advantage of this provision.
18 November 1939	Canada [births and deaths]	Margaret (Eleanor) Atwood, Canadian novelist, poet, short-story writer, and critic, born in Ottawa, Ontario, Canada.
30 November 1939	USSR, Finland [World War II (1939–45)]	The USSR invades Finland, with its main offensive to the north of Lake Ladoga. Finland responds by declaring war on the USSR.
13 December - 17 December 1939	UK, Germany, Uruguay [World War II (1939–45)]	The British heavy cruiser Exeter and light cruiser Ajax, and the New Zealand light cruiser Achilles engage the German ‘pocket battleship’ Graf Spee in the Battle of the Rio de la Plata (River Plate) in South America. It ends with the scuttling of the German warship off Montevideo, Uruguay.