Directory

1939 CE

A year that began with the final collapse of the Spanish Republic and ended with the outbreak of the Second World War following Germany's invasion of Poland, while Einstein warned Roosevelt of the potential for atomic weapons.

Geopolitics & Diplomacy

  • Germany invaded Poland on September 1, triggering declarations of war by Britain and France on September 3 and beginning the Second World War in Europe.
  • The Molotov-Ribbentrop Pact was signed on August 23, a non-aggression agreement between Nazi Germany and the Soviet Union that secretly divided Eastern Europe into spheres of influence.
  • Germany occupied the remainder of Czechoslovakia in March, violating the Munich Agreement and demonstrating that appeasement had failed.
  • Britain and France guaranteed the independence of Poland in March, pledging military support in the event of German aggression.
  • Albert Einstein signed a letter to President Roosevelt on August 2, warning that Germany might develop atomic weapons and urging the United States to begin its own nuclear research program.
  • The Soviet Union invaded Finland on November 30, beginning the Winter War after Finland refused Soviet territorial demands.
  • Italy invaded and occupied Albania in April, extending Mussolini's control across the Adriatic Sea.
  • Franco's forces captured Madrid and the remaining Republican-held cities in March and April, ending the Spanish Civil War with a Nationalist victory.
  • Britain issued the White Paper on Palestine in May, limiting Jewish immigration and land purchases and angering both Jewish and Arab communities.
  • The United States declared its neutrality in the European war but amended the Neutrality Act in November to allow arms sales to belligerents on a cash-and-carry basis, effectively aiding Britain and France.

Conflict & Security

  • The German invasion of Poland employed blitzkrieg tactics, with coordinated air and armored assaults overwhelming Polish defenses within weeks.
  • The Soviet Union invaded eastern Poland on September 17 under the terms of the secret protocol of the Molotov-Ribbentrop Pact, partitioning the country between Germany and the Soviet Union.
  • Warsaw surrendered on September 27 after weeks of bombardment and siege, with the last organized Polish resistance collapsing by early October.
  • The Battle of the River Plate in December was the first major naval engagement of the war, with British cruisers forcing the German pocket battleship Admiral Graf Spee to seek refuge in Montevideo.
  • The crew of the Admiral Graf Spee scuttled their ship in the harbor of Montevideo on December 17 rather than face the waiting British warships.
  • The Battles of Khalkhin Gol from May to September saw Soviet forces decisively defeat Japanese troops on the Manchukuo-Mongolia border, discouraging Japanese expansion northward.
  • The Winter War between Finland and the Soviet Union began in November, with Finnish forces mounting a fierce defense against the much larger Soviet army.
  • The Spanish Civil War ended in April with Franco's complete victory, establishing a dictatorship that would last until 1975.
  • Britain began evacuating children from London and other major cities in September in anticipation of German bombing raids.
  • The period from September 1939 through the spring of 1940 was called the Phoney War, as little fighting occurred on the Western Front despite the formal state of war.

Economy & Finance

  • The outbreak of war in Europe stimulated industrial production in the United States, with orders for military equipment and supplies boosting the economy.
  • Britain imposed wartime economic controls including rationing, price controls, and the direction of labor toward essential war industries.
  • Germany's war economy mobilized industrial resources for military production, though full wartime mobilization would not occur until later years.
  • The United States GDP grew as defense spending increased and European orders for American manufactured goods expanded.
  • France mobilized its economy for war, with the government imposing controls on production, prices, and the allocation of raw materials.
  • The Trans-Iranian Railway was completed in August, connecting the Persian Gulf to the Caspian Sea and later serving as a vital Allied supply route.
  • Gold reserves flowed to the United States as European nations purchased American goods and sought a safe haven for their assets.
  • Japan's economy remained on a war footing, with the ongoing conflict in China consuming a significant portion of national resources.
  • The Soviet economy continued its industrial buildup under the third Five-Year Plan, with military production receiving high priority.
  • The Hewlett-Packard Company was founded in a garage in Palo Alto, California, beginning as a small electronics firm.

Technology & Infrastructure

  • Pan American Airways inaugurated the first transatlantic passenger air service in June, flying Boeing 314 Clipper flying boats from New York to Marseille via the Azores and Lisbon.
  • Igor Sikorsky flew the VS-300, the first practical single-rotor helicopter, on September 14 in Stratford, Connecticut.
  • Television was demonstrated to the American public at the New York World's Fair, with NBC broadcasting the opening ceremonies on April 30.
  • The Heinkel He 178 made the world's first flight powered by a turbojet engine on August 27 in Germany.
  • Regular television broadcasting began in the United States, with NBC launching scheduled programming from the New York World's Fair.
  • The development of radar technology accelerated in Britain, with the Chain Home radar network providing early warning coverage of the English coast.
  • The magnetron cavity was under development in Britain, leading to advances in microwave radar technology.
  • The LaGuardia Airport opened in New York City in December, providing the city with a modern commercial aviation facility.
  • The Pennsylvania Turnpike was under construction as one of the first limited-access highways in the United States.
  • The development of synthetic rubber advanced as nations recognized the strategic importance of rubber supplies in wartime.

Science & Discovery

  • Lise Meitner and Otto Frisch published their theoretical explanation of nuclear fission in January, correctly describing the process by which uranium nuclei split.
  • Niels Bohr announced the discovery of nuclear fission to the American scientific community at a conference in Washington in January, sparking intense research activity.
  • The Einstein-Szilard letter warned President Roosevelt of the potential for nuclear chain reactions to be used in powerful weapons, contributing to the initiation of American nuclear research.
  • The first successful splitting of uranium atoms was replicated at multiple laboratories in the United States and Europe in the weeks following the publication of Meitner and Frisch's paper.
  • Ernest Lawrence was awarded the Nobel Prize in Physics for his invention of the cyclotron and the results obtained with it in nuclear physics.
  • DDT's insecticidal properties were discovered by Paul Hermann Muller, opening a new chapter in pest control and disease prevention.
  • The element francium was discovered by Marguerite Perey at the Curie Institute in Paris, the last naturally occurring element to be identified.
  • Research on penicillin production advanced at Oxford under Howard Florey and Ernst Boris Chain, who began systematic efforts to produce the antibiotic in useful quantities.
  • The Advisory Committee on Uranium was established by President Roosevelt in October to investigate the military potential of nuclear fission.
  • Astronomers continued mapping the structure of the Milky Way galaxy using radio and optical observations.

Health & Medicine

  • Howard Florey and Ernst Boris Chain began their systematic research on penicillin at Oxford, working to produce the antibiotic in quantities sufficient for clinical use.
  • The Rh blood group factor was described by Philip Levine and Rufus Stetson, leading to improved safety in blood transfusions and understanding of hemolytic disease of the newborn.
  • DDT was identified as a potent insecticide with potential applications in controlling malaria-carrying mosquitoes and other disease vectors.
  • Sulfathiazole was introduced as a new sulfonamide drug, expanding the range of bacterial infections treatable with antibacterial agents.
  • The development of blood plasma storage and transfusion techniques continued, anticipating the wartime need for battlefield blood supplies.
  • Polio outbreaks continued in the United States and Europe, with the disease causing paralysis and death, particularly among children.
  • Tuberculosis remained a leading cause of death worldwide, with effective antibiotic treatment still several years away.
  • Public health infrastructure expanded in the United States under New Deal programs, with new hospitals and clinics serving underserved communities.
  • Wartime preparations included stockpiling medical supplies and training military medical personnel in anticipation of casualties.
  • Research on nutrition and vitamin deficiency diseases continued, with fortification of staple foods gaining support as a public health measure.

Climate & Environment

  • Atmospheric carbon dioxide levels stood at approximately 309 parts per million.
  • A severe drought affected parts of Australia, contributing to widespread bushfires and agricultural losses.
  • Dust Bowl conditions continued to ease in the American Great Plains as soil conservation practices and improved rainfall aided recovery.
  • A powerful earthquake measuring 7.8 on the Richter scale struck Erzincan, Turkey on December 26, killing approximately thirty-three thousand people.
  • The outbreak of war in Europe led to immediate environmental consequences, including the mining of harbors and the disruption of fishing grounds.
  • Reforestation efforts continued in the United States under the Civilian Conservation Corps, with millions of trees planted since the program's inception.
  • The Kings Canyon National Park was established in California, protecting the deep granite canyons and giant sequoia groves of the southern Sierra Nevada.
  • Severe flooding struck parts of China as the Sino-Japanese War disrupted flood control infrastructure along major rivers.
  • Air pollution remained a chronic problem in industrial cities, with coal smoke and factory emissions degrading urban air quality.
  • Wildlife conservation efforts continued in the United States, with the Fish and Wildlife Service managing an expanding system of national refuges.

Culture & Society

  • The global population was approximately 2.3 billion, on the eve of a war that would claim tens of millions of lives over the next six years.
  • You Can't Take It with You won the Academy Award for Best Picture at the ceremony held in February.
  • The film Gone with the Wind premiered in Atlanta on December 15, becoming the highest-grossing film of its era and a landmark in cinema history.
  • The New York World's Fair opened in April with the theme of the World of Tomorrow, showcasing futuristic technology and attracting millions of visitors.
  • The Wizard of Oz premiered in August, introducing audiences to Technicolor fantasy and producing enduring cultural touchstones.
  • John Steinbeck published The Grapes of Wrath, a novel depicting the suffering of Dust Bowl migrants that won the Pulitzer Prize for Fiction.
  • Batman made his first appearance in Detective Comics No. 27 in May, becoming one of the most enduring characters in popular culture.
  • Marian Anderson performed a concert at the Lincoln Memorial on April 9 before an audience of seventy-five thousand after being denied the use of Constitution Hall by the Daughters of the American Revolution.
  • James Joyce's novel Finnegans Wake was published in May after seventeen years of composition, representing the extreme of literary modernism.
  • The first NCAA basketball tournament was held in March, with the University of Oregon winning the inaugural championship.