1. Struggles for power among European empires caused a World War.
EQ: What were the causes of WW1?
EQ: What methods of fights did the Allied and Central Powers use?
EQ: Why did the United States enter WWI?
SS5H4a

2. Causes of the War
 In the early 1900s nationalism was leading European countries to war.
 Countries such as Germany, Russia, and France competed for land and power.
To protect their empires, the nations started build up their armies which is called militarism.
They also began to form alliances.

3. The War Begins
 The two most important alliances were the Allied powers, or Allies, and the Central Powers.
In 1914, Austria-Hungary, one of the central powers, declared war on Serbia. Serbia had an alliance with Russia, so Russia fought on Serbia’s side. Then, Germany, also a Central Power invaded Belgium and France. France was allied with Russia. World War I had begun.

4. Allied and Central Powers
The Allied Powers
Russia
France
Italy
Great Britain
Romania
Serbia
Portugal
The Central Powers
Germany
Austria- Hungary
Bulgaria
The Ottoman Empire

5. The Battlefield  When the war began many people were eager for war.
 Because of strong Nationalism in Europe, thousands of young men signed up to serve in the military.
 Soldiers on both sides fought in long narrow ditches called trenches.
 This was called trench warfare.

6. The Battlefield Millions of Soldiers were killed in these battles.
The fighting lasted for 4 years.
 With trench warfare soldiers lived in the trenches day and night.
 The mud, cold weather and rats made life hard.

8. America Enters the War
When WWI started in 1914 most Americans wanted to stay out of it.
 In 1915 a German submarine sank the Lusitania. It was a British passenger ship with many Americans on Board. People were shocked and angry.
 The United States entered World War I in 1917 on the side of the Allies.

9. New Weapons
Machine Guns
Hand Grenades
Tanks
Submarines
Airplanes

10. Show What You Know Time EQ: What were the causes of WW1?
EQ: Why did the United States enter WWI?
Bonus: What methods of fights did the Allied and Central Powers use?
SS5H4a