The League of Nations (1920–1946)
The first worldwide intergovernmental organization, founded to preserve peace after World War I. Its humanitarian and technical work endured, while its handling of the Manchuria, Ethiopia, and Finland crises defined the limits of collective security without great-power commitment.
Events
The Covenant of the League Is Signed
The Covenant, drafted at the Paris Peace Conference largely around a plan promoted by U.S. President Woodrow Wilson, was signed as Part I of the Treaty of Versailles. It committed members to collective security, arbitration of disputes, open diplomacy, and reductions of armaments.
Location: Versailles, France
The United States Senate Rejects Membership
The U.S. Senate voted against ratification of the Treaty of Versailles, keeping the League's chief sponsor out of the organization. Opponents objected to Article X's collective-security commitments; supporters argued U.S. absence would weaken enforcement. The United States never joined.
Location: Washington, D.C., United States
The League Comes Into Force and Holds Its First Assembly
The League formally came into being on January 10, 1920, and its headquarters were established in Geneva. The first Assembly opened on November 15, 1920 with 41 member states represented, the widest gathering of governments in a permanent organization to that date.
Location: Geneva, Switzerland
The Aaland Islands Settlement
The League settled a dispute between Finland and Sweden over the Swedish-speaking Aaland Islands, awarding them to Finland with minority guarantees after a pioneering fact-finding commission. The case became a cited precedent for international arbitration.
Location: Geneva, Switzerland
The Corfu Crisis
After the murder of an Italian boundary commissioner, Italy bombarded and occupied Corfu. The Conference of Ambassadors, not the League, arranged a Greek apology and indemnity, and Italy withdrew. The episode, in which a great power received the settlement it demanded, marked an early blow to the League's authority over its own members.
Location: Corfu, Greece
Japan Invades Manchuria and the League Investigates
Following the Mukden Incident, Japanese forces occupied Manchuria and established the state of Manchukuo. The League dispatched the Lytton Commission, which found Japan in the wrong; the Assembly adopted its report in February 1933, and Japan announced its withdrawal from the League in March 1933. No enforcement measures followed.
Location: Manchuria, China
Italy Invades Ethiopia and Sanctions Are Imposed
Italy invaded Ethiopia from Eritrea. The League declared Italy the aggressor and imposed partial economic sanctions, while member governments ruled out an oil embargo and kept the Suez Canal open. Ethiopia's emperor, Haile Selassie, addressed the Assembly in June 1936; sanctions were abandoned that July.
Location: Ethiopia
The Soviet Union Is Expelled Over the Invasion of Finland
The Assembly expelled the Soviet Union, the only member ever expelled, after its invasion of Finland. The vote came three months into the European war, when the League's remaining capacity to enforce decisions was negligible.
Location: Geneva, Switzerland
The League Dissolves and Transfers Its Mandates to the United Nations
At its final Assembly in Geneva, the League voted itself out of existence, transferring assets, technical organizations, and its mandate system to the new United Nations. The UN Charter, drawn with the League's record in view, gave the Security Council enforcement powers the Covenant had not.
Location: Geneva, Switzerland