League of Nations Founded

The League of Nations, formally established in January 1920, was the first worldwide intergovernmental organization created to maintain peace through collective security and diplomacy. Though it ultimately failed to prevent another world war, its structures and ambitions shaped the United Nations and much of modern international law and cooperation.

The League emerged from the trauma of the First World War, which killed millions and shattered the old European balance of power. Proposals for an international body to prevent war had circulated for years among politicians, lawyers, and peace advocates in Britain, the United States, and elsewhere. U.S. President Woodrow Wilson became its most prominent champion, making a "general association of nations" the last of his Fourteen Points in 1918. The Covenant of the League was drafted at the Paris Peace Conference and written into the Treaty of Versailles and the other postwar settlements, so that the organization was tied directly to the peace itself.

The League came into being when the Treaty of Versailles took effect in January 1920, with its headquarters in Geneva, Switzerland. Its main bodies were an Assembly in which all members were represented, a smaller Council dominated by the major powers, and a Secretariat. Related institutions included the Permanent Court of International Justice and the International Labour Organization. Members pledged to settle disputes peacefully and to act together against aggression, using measures such as economic sanctions.

The United States never joined. Wilson's treaty failed to win the two-thirds Senate majority required for ratification, as opponents objected to commitments that they feared could draw the country into foreign wars and limit Congress's power to declare war. Germany and Soviet Russia were initially excluded, though Germany joined in 1926 and the Soviet Union in 1934. Lacking the United States and with its membership shifting, the League had to rely on Britain and France, which were often reluctant to commit force.

The League achieved real successes in the 1920s, resolving several smaller border disputes, aiding refugees, and promoting work on health and labor standards. But it had no army of its own and required agreement among members to act. In the 1930s it failed to stop Japan's seizure of Manchuria, Italy's invasion of Ethiopia, and the aggression of Nazi Germany. Japan, Germany, and Italy all withdrew. The outbreak of World War II in 1939 showed that it had not secured lasting peace, and it was formally dissolved in 1946. Many of its agencies, personnel, and lessons passed to the United Nations, which was designed with stronger enforcement powers in the Security Council.