The main aim of the League of Nations was to promote international cooperation and maintain lasting peace following World War I. Established in 1920 as part of the Treaty of Versailles, the League sought to prevent conflicts through collective security and diplomatic dialogue. It aimed to resolve disputes between nations peacefully and uphold territorial integrity and political independence. While it did succeed in several humanitarian efforts and some conflict resolutions, it ultimately failed to prevent aggression from major powers, notably during the 1930s, leading to its dissolution after World War II and the establishment of the United Nations.