World War 1 Crossword

What was the name of the boat sank by the Germans that triggered the U.S. to enter the war?
This weapon was the most useful invention in the trenches.
Where was the archduke Francis Ferdinand assassinated?
What was the name of the alliance made by Germany and Austria-Hungary?
What were planes first used for in world war 1?
What is extreme pride in your own country?
What was the name of the alliance between France, Britain, Russia, and later the U.S.?
What was the first kind of poison gas in world war 1 called?
The majority of deaths in World War 1 were...
Men who gave quick speeches at public events to demonize the German's were...
Making preparations for war is called..
Long ditches in the ground where soldiers lived and fought during the war were called...
Information in the form of posters, movies, and radio announcements intended to sway public opinion is called...
This invention was in direct response to the stalemate.
German submarines were called...