World War 1

2. A major 1916 battle known for extremely high casualties
4. U.S. President Woodrow Wilson's plan for peace after the war
6. Soldiers kept back from the front line to replace others or reinforce attacks
8. A royal title; Archduke Franz Ferdinand's death triggered world war 1
10. German submarines used to attack enemy ships
12. When a country seeks to expand its power by taking over other lands
14. The city where Archduke Franz Ferdinand was assassinated
16. Hiding soldiers or equipment by blending in with surroundings
18. The alliance of Britain, france, and Russia before the war
20. The area where opposing armies directly face each other in battle

1. The murder of an important person
3. A British passenger ship sunk by a German U-boat in 1915
5. Information or images used by governments to influence peoples opinion and support the war
7. A condition soldiers suffered from due to constant explosions and stress
9. The dangerous open area between 2 opposing trenches
11. Large weapons like cannons used to fire shells over long distances
13. Strong pride in ones country, sometimes leading to conflict with others
15. Countries that fought together against the central powers
17. a long and deadly battle between France and Germany
19. A type of fighting where soldiers lived and fought from long trenches to protect themselves from enemy fire