The Sudetenland was part of Germany until 1806 and of the German Confederation between 1815 and 1866. After the First World War the Sudetenland (some 11,000 square miles) became part of Czechoslovakia.
Until Adolf Hitler came to power most Sudenten Germans were content to remain in Czechoslovakia but in 1935 a Sudten-German Party, financed from within Nazi Germany, began to complain that the Czech-dominated government discriminated against them. German's who had lost their jobs in the depression began to argue that they might be better off under Hitler.
Adolf Hitler wanted to march into Czechoslovakia but his generals warned him that with its strong army and good mountain defences Czechoslovakia would be a difficult country to overcome. They also added that if Britain, France or the Soviet Union joined on the side of Czechoslovakia, Germany would probably be badly defeated. One group of senior generals even made plans to overthrow Hitler if he ignored their advice and declared war on Czechoslovakia.
In September 1938, Neville Chamberlain, the British prime minister, met Hitler at his home in Berchtesgaden. Hitler threatened to invade Czechoslovakia unless Britain supported Germany's plans to takeover the Sudetenland. After discussing the issue with the Edouard Daladier (France) and Eduard Benes (Czechoslovakia), Chamberlain informed Hitler that his proposals were unacceptable.
Adolf Hitler was in a difficult situation but he also knew that Britain and France were unwilling to go to war. He also thought it unlikely that these two countries would be keen to join up with the Soviet Union, whose communist system the western democracies hated more that Hitler's fascist dictatorship.
Benito Mussolini suggested to Hitler that one way of solving this issue was to hold a four-power conference of Germany, Britain, France and Italy. This would exclude both Czechoslovakia and the Soviet Union, and therefore increasing the possibility of reaching an agreement and undermine the solidarity that was developing against Germany.
The meeting took place in Munich on 29th September, 1938. Desperate to avoid war, and anxious to avoid an alliance with Joseph Stalin and the Soviet Union, Neville Chamberlain and Edouard Daladier agreed that Germany could have the Sudetenland. In return, Hitler promised not to make any further territorial demands in Europe.
The German Army marched into the Sudetenland on 1st October, 1938. As this area contained nearly all Czechoslovakia's mountain fortifications, she was no longer able to defend herself against further aggression.