| A | B |
| imperialism | greed for territory led to rivalries in Europe |
| nationalism | pride in your country became trying to be the best |
| militarism | preparing for war and building of armies, weapons and strategies |
| alliances | a tangles web of agreements between countries |
| balance of power | the desperate attempt to keep all countries equal |
| stalemate | neither side is able to gain an advantage |
| neutrality | when a country does not take sides |
| Lusitania | a US passenger ship sunk by the Germans |
| Bolshevik Revolution | the war where the communists took over |
| Russian Revolution | the war when the czar was thrown out |
| Sussex Pledge | Germany agreed not to sink any more US ships |
| Zimmermann Note | a mislaid letter from Germany to Mexico asking them to fight the US |