The Treaty of Versailles was the treaty that ended WWI. Germany was one of the countries that lost the war, and, under the treaty, it was forced to pay severe reparations (compensation for the money the victorious countries had spent). Germany, to pay this gargantuan sum, had to churn out a huge amount of money. This made German money (marks) practically useless. To put its uselessness in perspective, people had to carry wheelbarrows of money around just to buy simple things, like a loaf of bread. Needless to say, Germans were unhappy with their country's economic plight. Then, a charismatic leader by the name of Adolf Hitler came along. He promised to restore Germany to its former glory. Germans were desperate for such a change, and many eagerly followed him. As he delivered on his promises--creating jobs, taking territory lost in WWI back, building up a strong military (which, by the way, was prohibited by the treaty)--more and more Germans supported Hitler. He invaded the Rhineland (area near the border of France and Germany) and the Sudetenland (area near the border of Germany and, then, Czechoslovakia). Then, once he invaded Poland, Britain and France declared war on Germany, which began WWII. This is how the Treaty of Versailles was a direct cause of WWII.
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