Otto Hahn and Fritz Strassmann discover the fission of uranium nuclei; Lise Meitner and Otto Frisch explain the process shortly after.
Britain, France, Italy and Germany agree to Germany's annexation of Czechoslovakia's Sudetenland, the high point of the appeasement of Hitler.
An organised pogrom against Jews across Germany and Austria destroys thousands of shops and synagogues, with about 30,000 people arrested.
Pablo Picasso completes Guernica in response to the bombing of the Basque town during the Spanish Civil War; it becomes an enduring anti-war icon.
German and Italian aircraft supporting the Nationalists bomb the Basque town of Guernica, an event depicted in Picasso's famous painting.
Nazi Germany and the Soviet Union sign a non-aggression pact with a secret protocol dividing Eastern Europe into spheres of influence.
Germany invades Poland, starting the deadliest conflict in human history, which ends with Japan's formal surrender on 2 September 1945.