Albert Einstein and Leó Szilárd write to Franklin D. Roosevelt, urging him to develop a nuclear weapon.
Tag: 1939
18 December 1939
The Battle of the Heligoland Bight, the first major air battle of World War II, takes place.
15 August 1939
The Wizard of Oz premiers at Grauman’s Chinese Theater in Los Angeles, California
1 September 1939
Adolf Hitler begins the program of systematic euthanasia of mentally ill and disabled people.
2 August 1939
Albert Einstein and Leó Szilárd wrote a letter to Franklin D. Roosevelt, urging him to develop a nuclear weapon.
23 August 1939
Germany and the Soviet Union sign the Molotov-Ribbentrop Pact, a non-aggression treaty.