Appeasement was one of the most important causes of WWII. Today people say that it was Chamberlain's appeasement that started the war. It is true to some extent because Chamberlain couldn't prevent the war. However, Chamberlain had actually began thinking to change his policy after the Munich agreement; he was forced to change his appeasement policy because many events happened in 1938-1939. Let's see how the events affected Chamberlain's Policy:
Events in Europe pressured Chamberlain to abandon appeasement. For example, Franco's victory in Spanish Civil War in February 28th, 1939 and Mussolini's invasion of Albania in April 13, 1939 gave Chamberlain a huge pressure. These showed Chamberlain that Fascist countries are tending to war. If Chamberlain kept appeasing Hitler, Franco and Mussolini would also start to demand. So, Chamberlain noticed that he couldn't appease any fascist countries any more. In addition Hitler's alliance between other countries urged Chamberlain to change his policy.
Pact of Steel on May 22nd with Italy Mussolini made Chamberlain to think that keeping appeasing is nothing but just make fascist countries growing. And Nazi-Soviet Non-Aggression Pact between Hitler and Lenin on August 23rd scared Chamberlain the most. Chamberlain hoped that Lenin and Hitler fight and destroy each other because he hated both fascism and communism. However, his hope was destroyed by the pact between the enemies. This urged Chamberlain and made him felt he must fight against them in order to stop them to take over the world. In fact, Hitler's invasion of Czechoslovakia in March 14th, 1939 shocked Chamberlain the most. This was the most significant event that made his stooped appeasement policy. Hitler betrayed Chamberlain by breaking Munich Agreement and simultaneously humiliated him. This was Chamberlain's last straw; he decided that he would no longer appease anyone. In fact after this invasion,