1. Causes of World War I

2. Background causes
Imperialism - Germany felt it deserved more colonies in Africa and Asia
Nationalism - Europeans had strong feelings of pride toward their own countries
Militarism - belief that a nation needs a large military
Alliances - Europe had divided into two opposing alliances: Central Powers - Austria-Hungary, Germany, the Ottoman Empire, and Bulgaria, Allies - Serbia, Russia, France, Great Britain, and Italy

3. Event that started WWI
June 28, 1914 Serbian shot and killed Archduke Franz Ferdinand, heir to Austria-Hungary
Austria declared war on Serbia, war began

5. How WWI was fought
Trench warfare - troops stayed in trenches and fired at each other. Trenches stretched across France to Switzerland
Also used: tanks, machine guns, poison gas, airplanes, and U-boats (German submarines)

6. Trenches
Machine Guns & Poison Gas Masks

7. Poison Gas

10. U Boats
Airplane & Zeppelin

11. America’s Path to War
Pres. Wilson wanted a policy of neutrality (refusing to take sides)
May 1915, German U-Boat torpedoed the British ship Lusitania, turning many Americans against Germany

12. Zimmermann Telegram Discovered by the British
Zimmermann Telegram Discovered by the British. Germany wanted Mexico to join war. In return, Germany would help Mexico their territories back from America.
March German submarines sank three American ships. Pres. Wilson declared war in April.