"The Treaty of Versailles (1919) was the peace treaty that officially ended World War I between the Allied and Associated Powers and the German Empire. After six months of negotiations, which took place at the Paris Peace Conference (1919), the treaty formalized the armistice signed with Germany in November 1918 in the Compiègne Forest. Although there were many provisions in the treaty, one of the more important and recognized ones required that Germany accept full responsibility for causing the war and, under the terms of articles 231-247, pay reparations to the Allies."
http://www.newworldencyclopedia.org/entry/Treaty_of_Versailles