Sudetenland was a line of mountains that provided protection for Czechoslovakia from invasions. Many Germans also lived in this area and were given rights by the Czech government. However, this was not enough for the German nationalists who revolted.
Hitler announces that he wants to invade and annex Sudetenland to protect the Germans’ rights. The loss of the heavily armed mountain region would mean disaster for Czechoslovakia since it would leave the country defenseless against Germany.
Hitler gathers France and Great Britain to join Sudetenland with Germany. As a result of Great Britain’s and France’s weak state, they appeased to Hitler’s offer and Sudetenland became part of Germany.