There has been much speculation about the cause of World War II. This article seeks to answer the question: what were the factors that led to the outbreak of war? This is one of the most defining moments of the 20th century, necessitating the completion of such studies. The in-depth study will include coverage of the causes, events surrounding it, results and the effects it had around the world. Many previous events, such as the Holocaust and the signing of the Treaty of Versailles, have been proposed as being among the factors that triggered the outbreak of war. Since many factors have been suggested as causing the war, this article examines the facts in an attempt to conclude the cause of this event. Secondary sources that have been written on the subject will be the methodology used to draw a solid conclusion. Criteria B: • World War II took place between 1939 and 1945 (Preston, 1321). • The rise of militaristic and totalitarian regimes in Japan, Italy and Germany contributed greatly to the outbreak of war (Casey, 365). • World War I may have ended, but most countries still had wounds to heal. They had to settle their scores (Preston, 1321). • Germany had been disappointed, Italy defeated and Japan's ego inflamed. They hoped to redeem themselves, even if that meant prospering at the expense of their neighbors. By posing as opponents of communism, they prevented the Democrats from preparing; from a military perspective (Casey, 365).• In 1919, Britain, Italy, France, and the United States met to discuss a treaty that they hoped would pave the way for peace in Europe. (Casey, 366).• The war guilt clause was one of the terms of the treaty under which Germany had to consent to the fact that it had caused the First World War. (Casey,...... middle of paper .. ....struggle for supremacy." War in History 10.3 (2003): 365-367. Print. "Causes of World War II." Causes of World War II. Np, nd Web. April 6, 2014. .Dowswell, Paul. Usborne's Introduction to the Second World War. London: Usborne, 2005. Print. : Haus Pub., 2010. Print. Preston, Paul. Spain, Germany and the Second World War (review). New York: DK Pub., 2004. Print. “World War II – Causes April 6.”. 2014. .