Social Studies - 2018-19

USII.7a - Causes of World War II

The student will apply social science skills to understand the major causes and effects of American involvement in World War II by

a) explaining the causes and events that led to American involvement in the war, including the attack on Pearl Harbor;

Adopted: 2015



Political and economic conditions in Europe following World War I led to the rise of fascism and to World War II.

The rise of fascism threatened peace in Europe and Asia.

As conflict grew in Europe and Asia, American foreign policy evolved from neutrality to direct involvement.


Causes of World War II

 Economic devastation in Europe resulting from World War I:

o Worldwide depression

o High war debt owed by Germany

o High inflation

o Massive unemployment

 Political instability marked by the rise of Fascism:

o Fascism is a political philosophy in which total power is given to a dictator; individual freedoms are denied; and nationalism and, often, racism are emphasized.

o Fascist dictators included Adolf Hitler (Germany), Benito Mussolini (Italy), and Hideki Tojo (Japan).

o These dictators led the countries that became known as the Axis Powers.

The Allies

 Democratic nations (the United States, Great Britain, Canada) were known as the Allies. The Soviet Union joined the Allies after being invaded by Germany.

 Allied leaders included Franklin D. Roosevelt and, later, Harry S. Truman (United States), Winston Churchill (Great Britain), and Joseph Stalin (Soviet Union).

Gradual change in American policy from neutrality to direct involvement

 Isolationism (Great Depression, legacy of World War I)

 Economic and military aid to Allies (Lend-Lease program)

 Direct involvement in the war

War in the Pacific

 Rising tension developed between the United States and Japan because of Japanese aggression in East Asia and the Pacific region.

 On December 7, 1941, Japan attacked the United States at Pearl Harbor.

 The United States declared war on Japan.

 Germany declared war on the United States.


Updated: May 16, 2018