Causes of World War I
This alliance system split Europe into two major groups before World War I.
Allied Powers and Central Powers
This president asked Congress to declare war on Germany in 1917.
Woodrow Wilson
This type of warfare involved soldiers fighting from long ditches.
Trench warfare
This 1916 battle became one of the bloodiest in history, fought mainly between Britain and Germany.
The Battle of the Somme
This organization was created to help prevent future wars after World War I.
League of Nations
This assassination in 1914 sparked World War I.
The assassination of Archduke Franz Ferdinand
This secret German message tried to convince Mexico to attack the United States.
Zimmermann Telegram
This deadly weapon could fire hundreds of bullets per minute.
Machine gun
This long French battle became known for the phrase “They shall not pass.”
The Battle of Verdun
Germany was forced to pay these costly damages after the war.
Reparations
This term describes a country's strong pride and loyalty that increased tensions in Europe.
Nationalism
Germany used these underwater boats to attack ships.
U-boats
This new weapon was first used to break through trenches and barbed wire.
Tank
This country left the war after a revolution in 1917.
Russia
This global conflict was partly caused by problems left unresolved after World War I.
World War II
This European country declared war on Serbia after Franz Ferdinand was killed.
Austria-Hungary
This British passenger ship was sunk by Germany in 1915, killing Americans.
Lusitania
This poisonous weapon caused choking and blindness on the battlefield.
Poison gas
This date in 1918 marked the official end of fighting in World War I.
November 11, 1918
This empire collapsed after losing World War I, ending centuries of rule in parts of Europe and the Middle East.
The Ottoman Empire
This “M” in the MAIN causes of World War I refers to building up armies and weapons.
Militarism
The United States fought on this side during World War I.
The Allies
This term described psychological trauma suffered by soldiers after battle.
Shell shock
This agreement officially ended World War I in 1919.
The Treaty of Versailles
This holiday in the United States was originally called Armistice Day.
Veterans Day