World War 1

3. Heavy guns used in land warfare.
4. The German foreign secretary who sent a telegram proposing an alliance with Mexico.
6. A British passenger ship sunk by a German submarine in 1915.
8. A poisonous weapon first used at Ypres in 1915.
9. The city where Archduke Franz Ferdinand was assassinated.
10. A situation in which neither side can gain an advantage.
12. Belgian city that was the site of several major battles.
16. The treaty that officially ended the war and placed heavy penalties on Germany.
17. An agreement signed in 1918 to cease fighting and end the war.
18. A prolonged war or period of conflict during which each side seeks to gradually wear out the other by a series of small-scale actions.

1. Archduke whose assassination in Sarajevo triggered the war's outbreak.
2. The belief that a country should maintain a strong military and be prepared to use it aggressively.
3. Agreements between nations for mutual defense, which pulled countries into the conflict.
5. The desire for a nation's people to have its own independent nation-state, which fueled tensions in Europe.
7. The policy of extending a country's power and influence through colonization or military force.
11. Payments made by Germany to the Allies for war damages.
13. Payments for war damages that Germany was forced to make.
14. A situation in which neither side can gain an advantage.
15. A rigid airship used by Germany for bombing raids.
16. The site of a major battle between Germany and France in 1916.