September 30, 1938: The Munich Agreement cedes the Sudetenland to Nazi Germany.
The Munich Agreement, signed just after 1:00 AM on September 30, is remembered as one of the most spectacular examples of the failure of appeasement. Naturally, Neville Chamberlain was a signer.
Under the threat of war, Czechoslovakia was forced to annex a border region of their country called the Sudetenland, mostly inhabited by ethnic Germans. The occupation of the Sudetenland by the Germany army (and evacuation of Czechoslovakians) was scheduled to be complete by October 10. This Czechoslovakian government did not have any say in the annexation, as only Germany, the U.K., France, and Italy were present at the conference.
The same day, after Chamberlain returned from Munich, he delivered his famous (and deliciously ironic) “peace for our time” speech.