1930

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.
1929–1935	United Kingdom [television]	Experimental television broadcasting begins in England.
1930	[thought and scholarship]	Russian revolutionary leader Leon Trotsky publishes Permanentnaia revoliutsiia/The Permanent Revolution.
c. 1930	United Kingdom [women's rights]	It becomes socially acceptable for women to wear trousers when playing golf or riding a horse.
1930	[exploration]	US anthropologist Margaret Mead publishes Growing Up in New Guinea.
1930	Italy [family planning]	Mussolini's regime outlaws the distribution of birth control information and abortions, but half a million abortions continue to be carried out in Italy every year.
1930	[family planning]	Pope Pius XI condemns contraception, but allows the use of the rhythm method for birth control.
1930	[fiction]	The US writer Katherine Anne Porter publishes her short-story collection Flowering Judas.
1930	[fiction]	The Austrian writer Robert Musil publishes the first part of his novel Der Mann ohne Eigenschaften/The Man Without Qualities. The final part appears in 1943.
1930	[fiction]	The English writer Agatha Christie publishes her novel Murder at the Vicarage, which introduces her amateur detective Miss Jane Marple.
1930	[fiction]	The US writer Dashiell Hammett publishes his novel The Maltese Falcon, a classic of US hard-boiled detective fiction.
1930	[fiction]	The German writer Hermann Hesse publishes his novel Narziss und Goldmund/Narcissus and Goldmund.
1930	[information technology]	US electrical engineer Vannevar Bush builds the differential analyser. The first analogue computer, it is used to solve differential equations. It is the forerunner of modern computers.
1930	[aircraft]	English inventor Frank Whittle patents a turbo-jet engine. It is later used on the first jet aeroplane.
1930	UK [biology]	English geneticist and statistician Ronald Fisher publishes The Genetical Theory of Natural Selection in which he synthesizes Mendelian genetics and Darwinian evolution.
1930	[chemistry]	Swedish biochemist Arne Wilhem Kaurin Tiselius invents electrophoresis. This process, also known as ‘cataphoresis’, is defined as the movement of electrically charged particles through a liquid under the influence of an applied electric field.
1930	USA [cinema and film]	The Motion Pictures Producers and Distributors of America, better known under president Will Hays as the Hays Office, adopts the Motion Picture Production Code, a self-regulatory code to give guidance on content issues in films, especially sex and religion.
1930	[economics]	English economist J M Keynes publishes his Treatise on Money.
1930	[literature and language]	Laura Elizabeth Ingalls Wilder publishes Little House on the Prairie.
1930	[painting]	The US artist Edward Hopper paints Early Sunday Morning.
1930	[painting]	The Russian artist Marc Chagall paints Lovers in the Lilacs.
1930	[painting]	The US artist Grant Wood paints American Gothic, which becomes an icon of US life, and Stone City, Iowa.
1930	[philosophy]	German philosopher Moritz Schlick publishes Fragen der Ethik/Problems of Ethics.
1930	United Kingdom [plays]	The play Private Lives, by the English writer and performer Noël Coward, is first performed, at the Phoenix Theatre in London, England.
1930	[political theory]	German political thinker Alfred Rosenberg publishes Der Mythus des 20 Jahrhunderts/The Myth of the 20th Century, one of the most influential expressions of Nazi doctrine.
1930	United Kingdom [radio]	Over 3 million people hold radio licences in Britain.
28 January - 30 January 1930	Spain [political events]	The Spanish dictator Primo de Rivera resigns following the army's withdrawal of its support, and the Liberal general Dámaso Berenguer forms a ministry (30 January) pledged to a restoration of democracy.
18 February 1930	[astronomy]	US astronomer Clyde Tombaugh, at the Lowell Observatory, Arizona, discovers the ninth planet, Pluto.
2 March 1930	[births and deaths]	D(avid) H(erbert) Lawrence, English poet and novelist, author of the controversial Lady Chatterley's Lover, dies in Vence, near Antibes, France (45).
12 March - 6 April 1930	India [political events]	The Indian nationalist leader Mahatma Gandhi opens a civil-disobedience campaign in India with his ‘Salt March’ (a march from Ahmedabad, Gujarat, to Dandi on the coast where, on 6 April, Gandhi seizes salt to protest at the levying of salt tax on poor people).
30 March 1930	Germany [political events]	Heinrich Brüning, leader of the Centre Party, forms a coalition of the right in Germany, replacing the Social Democrats, but without a majority in the Reichstag (parliament).
3 April 1930	Ethiopia [political events]	Ras Tafari, regent of Ethiopia, becomes emperor on the death of Empress Zauditu; he assumes the name Haile Selassie (‘Might of the Trinity’).
19 May 1930	South Africa [suffrage]	White women are enfranchised in South Africa.
31 May 1930	[births and deaths]	Clint Eastwood, US actor, director, and producer, star of many westerns, born in San Francisco, California.
8 June 1930	Romania [political events]	Crown Prince Carol, strongly supported by the army and the peasantry, is elected king of Romania as Carol II by the national assembly, which sets aside his son Michael, king since 1927.
11 June 1930	[transport]	The first bathysphere, a spherical steel craft for undersea exploration, built by US zoologist William Beebe and US engineer Otis Barton, descends to 435 m/1,428 ft.
17 June 1930	[legislation]	The US president Herbert Hoover signs the Smoot–Hawley Tariff Act, raising duties on some 890 agricultural and manufactured items.
7 July 1930	[births and deaths]	Arthur Conan Doyle, Scottish novelist who created the detective Sherlock Holmes, dies in Crowborough, Sussex, England (71).
5 August 1930	[births and deaths]	Neil Armstrong, US astronaut and the first person to set foot on the Moon (1969), born in Wapakoneta, Ohio.
6 August 1930	Canada [political events]	Following the general election victory of the Conservatives in July, the Liberal leader William Mackenzie King resigns as prime minister of Canada; he is succeeded by the Conservative leader Richard B Bennett.
25 August - 27 August 1930	Peru [political events]	Following a revolt by an army garrison, a military junta takes power in Peru and forces Augusto Leguía to resign the presidency. Colonel Luis Sánchez Cerro, leader of the original revolt, becomes president on 27 August after marching on the capital Lima.
3 September 1930	USA [railways]	US inventor Thomas Edison installs an experimental electric passenger train on the Lakawanna Railroad in New Jersey.
6 September 1930	Argentina [political events]	Demonstrations by crowds in Buenos Aires and a revolt by the army force President Hipólito Irigoyen of Argentina to resign; General José Uriburu is appointed president.