Nazi foreign policy aimed to revise the Treaty of Versailles, unite German-speaking people and expand German land. This led to the invasion of the Rhineland, the Austrian Anschluss and the crisis in Czechoslovakia. Britain and France's policy of appeasement led to the Munich Agreement.
Britain did not act. There were a number of reasons for this:
at the time, Britain was in dispute with Italy over its military campaigns in Abyssinia (Ethiopia) and British forces had been moved into the Mediterranean in case Italy became aggressive. There was little Britain could do to stop Germany
during the 1930s a policy of appeasement was followed by a succession of British Governments. This meant that the British would seek to negotiate or discuss issues with Germany in an effort to avoid another war. This was popular with sections of the British population as they remembered the huge casualties of the Great War
the British politician Lord Lothian stated that the Germans were only going into their own back garden. This was a popular view of the German reoccupation of the Rhineland. Although the British government denounced the breaking of the terms of Versailles, they did not think it merited war
France did not act. France was between governments when Germany re-occupied the Rhineland. The Hoare-Laval fiasco (where France and Britain tried to appease Italy's leader Mussolini by agreeing to offer him land in Abyssinia) had been deeply unpopular and had eventually brought down the government. France could not act to stop the Germans.
French military forces had previously been moved from the Rhine to the Alps and Tunisia because of the political tension with Italy. As such, their forces near the Rhineland were weakened.
French generals also thought the German occupying forces were much bigger than they actually were. They would not attack without more support.
the French would only act on Germany with Britain's aid. British reluctance to stand up to Hitler meant the French also took no action. France placed its faith in the Maginot Line of fortifications on the Franco-German border.
Hitler had significantly improved his status.
Over the next two years the Germans built defences and within 18 months their rate of rearmament passed that of Britain and France. He did not agree to an Air Force Pact with Britain. He began to think he was infallible.
the reoccupation of the Rhineland made it more difficult for Britain and France to take future action against Germany. After 1936 Hitler ordered a line of defences to be built along Germany’s western frontier. This became known as the West Wall or Siegfried Line
the reoccupation of the Rhineland was seen as an occasion when France was directly threatened by Hitler’s actions. The lack of reaction by France suggested that they were unlikely to take action over any future aggression in Eastern Europe
France continued to strengthen the Maginot Line in an attempt to safeguard against future German aggression
France's alliance with Britain became strained due to Britain's refusal to stand up to Germany
French alliances with eastern European countries were undermined as France concentrated solely on defence against possible German aggression
Italy formed the Rome-Berlin Axis in July 1936
Hitler signed the Anti-Comintern Pact with Japan in November 1936 which formed an anti-Communist alliance between the two nations
Britain promised France and Belgium help if they were invaded (reaffirming Locarno)