When Hitler sent troops into the Rhineland in 1936, other European nations offered no resistance. This was due to a combination of factors, including the belief that the German occupation of the Rhineland was justified and the reluctance to engage in military conflict.
When Hitler annexed Austria in 1938, the other European nations, including the major powers, did not respond with immediate armed resistance. Instead, they chose to appease Hitler's territorial ambitions in the hopes of avoiding war. This led to the signing of the Munich Agreement and the convening of the Munich Conference in September 1938.
At the Munich Conference, the leaders of Britain, France, Italy, and Germany gathered to negotiate a resolution to the escalating tensions over Czechoslovakia. In an attempt to maintain peace, the European powers agreed to appease Hitler once again and allowed Germany to annex the Sudetenland region of Czechoslovakia. This decision was met with criticism by some, as it was seen as sacrificing Czechoslovakia's sovereignty in favor of appeasement.