Historians state that World War II was the deadliest and most destructive war the world has ever seen. More than 50 nations took part in the war, and more than 38 million people died. Understanding the causes and course of World War II is a high emphasis topic on the TASC Test Assessing Secondary Completion™ Social Studies subtest.
Causes of World War II
When Britain and France declared war on Germany after it invaded Poland in September 1939, World War II had officially begun.
The following events fueled the inception of World War II:
- Failure of peace efforts. After World War I, attempts were made to achieve stable world peace. The League of Nations, established in 1920, was a forum in which nations could settle their disputes. However, the League had no real power and could only try to persuade the offending nation to concede. If efforts came up short, they could impose economic sanctions on that country. But the League had so little power that the sanctions it passed were normally ignored, and it could do nothing from that point on.
- Rise of fascism. Fascism is a governmental system led by a dictator having complete power, forcibly suppressing opposition and criticism, regimenting all industry, commerce, etc., and emphasizing an aggressive nationalism and often racism. The rise of fascism in Italy under Benito Mussolini and Germany under Adolf Hitler brought the world to the brink of war. People who listened to these dictators believed they could be brought to world domination.
- Formation of the Axis Coalition. The Axis Coalition, or Axis Powers, began to form in 1936. Germany and Italy signed a friendship treaty that formed the Rome-German Axis. Shortly after, Japan and Germany signed a treaty against communism called the Anti-Comintern Pact. Germany and Italy signed an even stronger alliance on May 22, 1939 called the Pact of Steel, later called the Tripartite Pact when Japan signed it on September 27, 1940. The three main Axis Powers, Germany, Italy, and Japan, were allies in the war.
- Worldwide depression. The costs of World War I, and the costs to rebuild Western Europe after years of fighting, resulted in enormous debts from Western European powers to the United States. When the stock market crashed in 1929, the United States recalled all foreign loans. Unable to repay these loans, the economies of the West collapsed, beginning the Great Depression.
Character of World War II: At Home and Abroad
For Americans, World War II had a clear-cut purpose: to defeat tyranny. “Most of Europe had been conquered by Nazi Germany, which was under the iron grip of Dictator Adolf Hitler. The war in Europe began with Germany's invasion of Poland in 1939. Wherever the Nazis went, they waged terror, mainly against Jews, but also against other minorities,” according to Scholastic.com.
Japanese armies invaded country after country, island after island, in Asia and the Pacific. The US was bombed on December 7, 1941 by Japanese planes on the soil of Pearl Harbor, Hawaii. The next day, the U.S. Congress declared war, officially pulling the U.S. into World War II.
Reshaping the U.S. Role in World Affairs
The war ended in Europe on May 7, 1945, when Germany surrendered. Japan surrendered on August 14, 1945 after the U.S. dropped two atomic bombs, one on Hiroshima and one on Nagasaki. The United States soared as a world super power after World War II. You can review the US post war domestic policy in a previous social studies TASC blog post.
As Scholastic.com notes, President Franklin D. Roosevelt, who had led the U.S. in wartime, did not live to see the peace. In a speech that was never delivered, he spoke of the need to preserve peace: "Today we are faced with the preeminent [above all other] fact that, if civilization is to survive, we must cultivate the science of human relationships — the ability of all peoples, of all kinds, to live together and work together in the same world, at peace."