| Term | Definition |
| Reparations | payment for damages after a war, Germany had to pay these to the Allies |
| Fourteen Points | Wilson's plan for world peace following World War I |
| League of Nations | An organization of nations formed after World War I to promote cooperation and peace. |
| War Guilt Clause | Germany had to accept blame for starting World War One |
| National Self-Determination | Belief that borders should be based on ethnicity or national identity |
| Three conditions of the Treaty Versailles | Germany lost territory, Germany had to pay reparations, Germany had to reduce the size of its military, Germany had to accept blame for the war |
| US Senate | body that rejected the Treaty of Versailles |
| The "Big Four" | The leaders of the US, Britain, France and Italy |