How did WWI cause WWII?

World War I led to the start of World War II. When World War I ended, the United States wanted to have a peace treaty that wouldn’t be harsh on Germany. However, Great Britain, France, and Italy wanted a treaty that would punish Germany. As a result, Germany had to pay a huge sum in reparations to the Allies. This crippled their economy and helped lead to the failure of the Weimar Republic after the war ended. Germany also had to give up land and reduce its military capabilities. The harsh treaty also created much resentment in Germany. These factors led to the rise of Adolph Hitler and the Nazi Party.
The Versailles Treaty created the League of Nations. This was supposed to be an organization designed to keep the peace after the war ended. However, the United States didn’t join the League of Nations. When Germany, Japan, and Italy became more aggressive in the 1930s, the League of Nations did nothing to stop this aggression. As a result, more aggression occurred, eventually leading to the start of World War II.
https://www.ducksters.com/history/world_war_ii/causes_of_ww2.php

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