1. World War I

2. In 1914, five factors made Europe a powder keg ready to explode.
Nationalism
Militarism
Economic rivalries
Imperial ambitions
Regional tensions 2

3. Nationalism, or devotion to one’s country, caused tensions to rise.
Some felt national identity centered around a single ethnic group and questioned the loyalty of ethnic minorities. 3

4. Economic competition caused a demand for colonies and military bases.
Economic competition for trade and colonies increased nationalistic feelings.
Economic competition caused a demand
for colonies and military bases. 4

5. Nations stockpiled new technology,
including machine guns, mobile artillery,
tanks, submarines, and airplanes.
Militarism,
combined with nationalism, led to
an arms race. 5

6. The Allied Powers included Britain, France, Russia, and Serbia.
Europe’s alliance system caused the conflict to spread quickly, creating two main combatants.
The Allied Powers included Britain, France, Russia, and Serbia.
The Central Powers included Germany and Austria-Hungary. 6

7. The era’s deadly defensive weapons made attacks difficult and dangerous.7

8. Many Americans favored one side or the other.
The United States had a long tradition of staying out of European conflicts.
As the war dragged on in Europe, President Wilson urged Americans to remain neutral.
Many Americans favored one side or the other. 8

9. U.S. public opinion fell into three main groups.
Isolationists
favored staying out of the war
Interventionists
favored fighting on the Allies’ side 9

10. German U-boats torpedoed ships bound for Britain.
On May 7, 1915, a U-boat sank the British passenger ship Lusitania off the coast of Ireland, killing many Americans.

11. Two events in 1917 led President Wilson to ask Congress to declare war on the Central Powers.
The Zimmermann note was intercepted. In this telegram, Germany tried to forge an alliance with Mexico against the United States.
Germany returned to a policy of unrestricted submarine warfare, sinking any ship headed for Britain. 11

12. United States entered World War I
On April 2, 1917, Wilson asked Congress to declare war against Germany, saying, “The world must be made safe for democracy.”
United States entered World War I 12

13. Home Front in World War I

14. How did World War I affect Americans at home?
The war permanently changed Americans’ relationship with their government. The federal government played a major role in Americans’ daily lives.

15. United States needed to increase the size of its army.
Congress passed the Selective Service Act.
More than 4 million U.S. soldiers were sent to Europe.

16. US encouraged farmers to produce more food to feed
the soldiers.
Women entered the workforce to help the war effort. 16

17. The government passed laws to discourage dissent.
The 1917 Espionage Act gave postal authorities power to ban newspapers or other printed materials that could incite treason.
In 1918, the Sedition Act outlawed speech that went against the government or the military.

18. The war effort presented new opportunities to individuals, including African Americans.
In the Great Migration, more than a million African Americans moved north, hoping to escape poverty and Jim Crow laws and find better jobs. 18

19. Women embraced the opportunities that became available during the war.
Women filled jobs that were vacated by men and participated in the war effort.
By proving that they could succeed in any type of job, women convinced President Wilson to support their demand to vote. 19

20. American Involvement in World War I

21. How did Americans affect the end of World War I and its peace settlements?
When the United States entered World War I in the spring of 1917, the war was at a deadly, bloody stalemate along the Western Front.
The American entry into the war would play a key role in the Allied victory.

22. Germany increased U-boat attacks, hoping to win the war before American troops could make a difference.
Convoys of British and American ships, protected by warships, provided better safety at sea. 22

23. By the fall of 1918, the German front was collapsing.
Germany surrendered to the Allies 23

24. Wilson’s Fourteen Points made specific proposals to promote future peace.
Practice open diplomacy.
Allow freedom of the seas.
Encourage free trade.
Reduce arms stockpiles.
Scale back colonialism.
Encourage self-determination of nations.
Establish a League of Nations.

25. However, Allied leaders at Versailles wanted reparations.
European leaders did not share Wilson’s vision of peace without victory.
They wanted Germany to pay for war damages. 25

26. Effects of World War I in the United States

27. What political, economic, and social effects did World War I have on the United States?
The Treaty of Versailles produced an unstable peace. Its harsh terms left Germany with a strong desire for revenge.
In the United States, the horrors of the war and the fear of radicals led people to question the nation’s role in the world.

28. Economic troubles also caused problems in the United States.
A recession, or economic slowdown, occurred after the war.
Many women and African Americans lost their jobs to returning soldiers.
Tension over jobs and housing led to race riots in some cities. 28

29. Several events combined to create the first Red Scare in the United States.
Violent strikes
The emergence of the Soviet Union as a communist country

30. One mail bomb was sent to Attorney General A
One mail bomb was sent to Attorney General A. Mitchell Palmer, who launched the Palmer Raids in 1920.
Police arrested thousands of people.

31. In the 1920 presidential election, Republican Warren G
In the 1920 presidential election, Republican Warren G. Harding based his campaign on a call for “normalcy,” a return to a simpler time before President Wilson. 31

32. Despite Harding’s desire to go back to earlier times, it became clear that a new world order had emerged.
Meanwhile, the United States was strong, confident, and prosperous. It became the world’s economic center and largest creditor nation. 32