| A | B |
|---|
| Militarism | the aggressive strengthening of armed forces |
| Archduke Francis Ferdinand | Heir to the throne of Austria-Hungary who was assassinated in 1914 |
| mobilize | to prepare the military for war |
| Central Powers | Austria-Hungary and Germany, later joined by Bulgaria and the Ottoman Empire |
| Allied Powers | France, Russia and Britain, later joined by Italy |
| Trench Warfare | defending a position by fighting from the protection of deep ditches |
| Stalemate | situation in which neither side can win |
| U-boats | German submarines |
| neutral | not favoring either side in a conflict |
| Lusitania | Ship sunk by a German U-boat in 1915 |
| Zimmermann Note | Secret telegram from the Germans to Mexico |
| Selective Service Act | law requiring some men to register to be drafted |
| Liberty bonds | bonds sold by the U.S. to raise money to provide loans to the Allies |
| National War Labor Board | helped workers and management avoid strikes and reach agreements |
