Appeasement is the policy of making concessions to dictatorial governments so as to avoid conflict.
Appeasement policy ruled Anglo-French foreign policy during the 1930s. Its main purpose was to avoid war but ended up allowing Hitler to extend German territory uncontrolled.
Appeasement policy could be understood in the context of weak collective security agreements made after World War I. But it was also caused by the public pressure for peace at any cost, the difficulty to set rearmament due to the Great Depression, and the admiration some British and French politicians had for Hitler and Mussolini.