I think the biggest cause of the war was Hitler's invasion of Czechoslovakia. There are many reasons that caused the Second World War. The main figure here was Adolf Hitler. He rearmed Germany, remilitarized Rhineland, took over Sudetenland, invaded in Czechoslovakia and finally pushed Germany, Europe and even the whole world into war. Among the several things he did, taking over Sudetenland and Czechoslovakia are two main causes of the war. In March 11, 1938, Hitler invaded …showed first 75 words of 692 total…

…showed last 75 words of 692 total…was ready for the war. Further more, because of the alliances (ex: Germany and Soviet Union signed alliance, Poland and Britain signed alliance), other countries in the world are involved. So when Germany invaded Poland later on, a world war declared again. Therefore, I think though both the Munich Agreement and Hitler's invasion of Czechoslovakia are quite big cause of the war, Hitler's invasion of Czechoslovakia was the biggest cause of the Second World War.