A very important factor which contributed to the war a great deal, were the peace treaties of 1919 and 1920. Although they were intended to reduce Germany's strength and decrease the risk of another war breaking out, the actually built up resentment amongst the aggressors (especially Germany) who, thinking the punishment unfair and humiliating, planned to take revenge on the allies. Even the British public agreed that the treaties were too harsh, which in the eyes of the British, justified Germany's actions for invading their previously owned territory. What insulted Germany even more, was that she was not allowed to attend the peace conference to determine their future.
             The problems the peacemakers had when writing the peace treaties, were (a) if they weren't brutal enough, they would not feel that Germany had suffered enough for creating a war, and (b) if they were too unreasonable, Germany wouldn't take the terms seriously and would cause a second world war. Instead of a sensible balance between the two, the treaties were overly demanding and resulted in a loss of communication between the two powers, for example, the amount of reparations Germany had to pay was totally unrealistic and they were suffering economic crisis. They claimed that they had been denied 'the equality of rights.'
             This aggression lead to the invasion of many European vicinities, many of which were taken away from Germany in the Versailles Treaty. These include the Sudetenland, the Rhineland and the Saar area (which contained lots of raw materials that were vital to Germany's expansion.)
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