There were many reasons leading up to World War II, and many of them were based on conditions of the Treaty of Versailles of 1919 following World War I (On). Article 10 of the treaty bound the allies to help other parties to the treaty in case of aggression. Germany was pressured by the guilt attributed to it fro World War I under Article 231 and the necessity of making compensation to the civilian populations injured in the war under Article 232. Another result of the Treaty of Versailles was the separation of many German speaking peoples from their homeland, and Hitler wanted to reunite these people so that all German speaking people could live in one united land (Fuller). After Austria lost the Sudetenland in the Treaty to St. Germain in 1919, leaving three million German speaking people in Czechoslovakia.
Hitler also wanted more land for living space for his countrymen (Fuller). Gaining Austria via the Anschluss and the Sudetenland by the Munich Agreement in 1938, Hitler's ambitions grew, and this led to his breaking the Treaty of Versailles, which led to World War II. Britain was initially sympathetic to Germany, appeasing Hitler's demands; France was reluctant to intervene because it felt it could not rely on Britain and America for support; and the United States was isolated.
The rearmament of Germany, the remilitarization of the Rhineland, Chamberlains appeasement policy to Germany, the Anschluss with Austria, and the annexation of the Sudetenland all broke the Treaty of Versailles and helped cause World War II (Fuller). These could all be considered unresolved issues left over from World War I and not settled to Germany's satisfaction by the Treaty of Versailles, meaning World War II was the result of unresolved issues from World War I.
Fuller, R. P. "Causes of the second world war." 11 May 2005. 2 Aug. 2005.
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