Dashed left edge = started before October 1939 ·
Dashed right edge = ongoing beyond October 1939
Events in October 1939 13
1869 – 1939Harvey Cushing (1869-1939)Died 7 October 1939, aged 70Cushing was an American surgeon who pioneered brain surgery and is known as the father of modern neurosurgery. He described Cushing's disease. He won a Pulitzer Prize for his biography of William Osler.
1872 – 1939Zane Grey (1872-1939)Died 23 October 1939, aged 67Grey was an American novelist whose Western romances did much to create the popular image of the American West. Riders of the Purple Sage was his best-known book. More than a hundred films were made from his stories.
1939New York World's Fair opensThe World of Tomorrow opens in QueensThe New York World's Fair opened at Flushing Meadows. Exhibits included television, the Futurama model of a future America and the Trylon and Perisphere. Its first season ended on 31 October, and it reopened in 1940.
1939Einstein–Szilárd letterRoosevelt is warned about atomic bombsAlbert Einstein signed a letter drafted by Leó Szilárd warning President Roosevelt that Germany might develop extremely powerful uranium bombs. Alexander Sachs delivered it to Roosevelt on 11 October. In response, Roosevelt set up the Advisory Committee on Uranium.
1939German invasion of PolandGermany attacks Poland without a declaration of warGerman forces crossed into Poland on 1 September, and the invasion is usually taken as the start of the Second World War in Europe. Polish forces were overwhelmed by attacks from the west, north and south. The last Polish field units surrendered on 6 October.
1939Invasion of PolandStart of WWIINazi Germany and the Soviet Union invaded Poland, marking the beginning of the Second World War.
1939First Battle of ChangshaChinese forces repel a Japanese offensive in HunanJapanese troops advanced on Changsha, the capital of Hunan, and were forced back by the National Revolutionary Army. It was the first big Chinese defensive success after the fall of Wuhan. Chinese morale improved as a result.
1939Soviet invasion of PolandThe Red Army invades eastern PolandUnder the secret terms of the Molotov–Ribbentrop Pact, Soviet forces entered eastern Poland on 17 September. Germany and the Soviet Union then divided the country between them. Hundreds of thousands of Polish soldiers were taken prisoner.
1939Aktion T4 authorisedHitler orders the killing of disabled peopleHitler signed an order in October, backdated to 1 September, that authorised doctors to kill patients judged incurable. Around 70,000 people were murdered in gas chambers under the programme by 1941. Its staff and methods were later used in the extermination camps.
1939Declaration of PanamaAmerican republics declare a neutral zone at seaThe foreign ministers of the American republics met in Panama and declared a security zone of several hundred miles around the Americas. They asked the warring powers to keep hostilities out of the zone. The Battle of the River Plate broke it two months later.
1939Sinking of HMS Royal OakA U-boat sinks a battleship inside Scapa FlowGünther Prien took U-47 into the Royal Navy's anchorage at Scapa Flow and torpedoed the battleship Royal Oak. 835 of her crew died. The attack exposed serious gaps in the base's defences.
1939Bill Monroe joins the Grand Ole OpryMule Skinner BluesWith his new band, the Blue Grass Boys.
1939 – 2006Ali Farka Touré (1939-2006)Died 6 March 2006, aged 66Ali Farka Touré, the Malian singer and guitarist celebrated for blending traditional West African music with blues, died of bone cancer in Bamako. He won multiple Grammy Awards for his collaborative albums. He is widely regarded as one of Africa's most influential musicians.