The treaty that marked the end of World War I was the Treaty of Versailles, signed on June 28, 1919. The treaty was negotiated at the Paris Peace Conference and placed heavy reparations and territorial losses on Germany, holding it responsible for the war. Along with the Treaty of Versailles, several other treaties were signed with Germany's allies, collectively shaping post-war Europe. The treaty also established the League of Nations, aimed at promoting peace and preventing future conflicts. However, its punitive measures against Germany contributed to economic and social instability, setting the stage for the rise of extremism and World War II later on.