After the United States went into a economic depression in the 1930's which resulted in a world wide depression.
The treaty of Versailles was created to end WW1, but it actually ended up being a factor of WW2. Italy was unhappy with the results of the treaty and Germany did not want to have full responsibility for the war.
After the Treaty of Versailles was created Italy was upset that they were not receiving land from Germany and Germany was mad they had to pay reparations. This resulted in Italy and Germany joining forces.
Joseph Stalin was the dictator of the Soviet Union. He also created a country wide famine.
Benito Mussolini became Prime Minister of Italy and caused Italy to fail as a country. He was then executed by Italian Partisans.
Adolf Hitler is known by most as a truly evil person. He is responsible for the death of thousands of Jewish people during the time he was in power. He created Nazi Germany and brought true destruction.