Below are some of the main causes of World War 2. Treaty of Versailles. The Treaty of Versailles ended World War I between Germany and the Allied Powers. Japanese Expansion. Fascism. Hitler and the Nazi Party. Appeasement. Great Depression. Interesting Facts about the Causes of World War 2. Activities. Click to see full answer. Consequently, what were the six long term causes of World War 2?The major causes of World War II were numerous. They include the impact of the Treaty of Versailles following WWI, the worldwide economic depression, failure of appeasement, the rise of militarism in Germany and Japan, and the failure of the League of Nations. what were the long term causes of World War 1? World War I began in June of 1914, and is considered to have five major causes that led to the outbreak of the war. These five causes include the four long-term causes (militarism, alliances, imperialism and nationalism) discussed in this reading and one short-term cause (the assassination of Franz Ferdinand). Then, what were the long and short term causes of ww2? Interrelations and economics Problems with the Treaty of Versailles. French security demands. Japan’s seizure of resources and markets. Failure of the League of Nations. The Mason-Overy Debate: “The Flight into War” theory. Nazi dictatorship. Re-militarization of the Rhineland. Italian invasion of Ethiopia (Abyssinia) What were the economic causes of World War 2? Economic Causes of WWII The Germans were unsatisfied with the terms of the treaty, as they were forced to: 1) Accept the blame for starting WWI (War Guilt Clause). 2) Pay 6.6 billion pounds in reparations, in coal, steel,agricultural products, and even intellectual property such as the patent for aspirin.