There were several factors responsible for the start of World War II. One factor was the desire for revenge as a result of the Versailles Treaty from World War I. The Germans believed they were treated unfairly and harshly by the terms of the treaty. The huge reparation payments significantly hurt the German economy. Germany resented that it had to take responsibility for the start of the war. Hitler used these perceived insults as a way to stoke German nationalism to avenge this mistreatment. Italy also believed that it didn’t receive enough land from the terms of the Versailles Treaty.
Another factor was the lack of a response to the aggressive actions of Germany, Italy, and Japan in the 1930s. The United States, Great Britain, and France were dealing with the impacts of the Great Depression and had to focus their energy on dealing with this economic crisis. In addition, none of the Allied nations were willing to risk going to war so soon after World War I ended. The lack of a response indirectly sent a message that could be interpreted by the leaders of Germany, Japan, and Italy as meaning that taking land was acceptable. The United States passed strict neutrality laws to prevent any involvement in another war. The European nations hoped that the threat might disappear and even tried to appease Germany when it signed the Munich Pact, allowing Germany to take control of the Sudetenland.
Germany, Japan, and Italy also wanted to expand their empires. One way to accomplish this goal was to go to war and gain land as a result of winning the war. By taking over countries and regions such as Manchuria, Ethiopia, Austria, and Albania, the Axis countries hoped they would keep control of these places after winning the war, as well as gaining control over other lands.