Unit 12: The Causes and Consequences of World War II
By the late 1930s, anti-democratic governments in Europe and Asia began to threaten the security of surrounding states. Nazi Germany occupied parts of Czechoslovakia and Austria in 1938. In 1939, Germany invaded Poland, and Britain and France quickly declared war in response, leading to the outbreak of World War II. In the Pacific, Japanese forces continued to expand their hold on China, and the military prepared invasion plans for European colonies in Southeast Asia. Meanwhile, the United States remained isolated from the growing conflict, as it had done during much of World War I.
America entered the war in December 1941 after a surprise Japanese attack on American military forces in Pearl Harbor, Hawaii. American troops joined British and French forces to invade Nazi-occupied Europe. In the Pacific, American and Allied forces eventually checked Japanese military expansion and began to go on the offensive. Like World War I, World War II was fought worldwide, with critical battles in Africa, Asia, Europe, and the Pacific.
In this unit, we examine the global impact of World War II and why the United States and Soviet Union emerged as economic, political, and military superpowers. We examine how the war reshaped political, economic, and social life in Europe and Asia and led to devastating new military technologies, such as the atomic bomb. Finally, we will discuss how Nazi anti-Semitic ideologies led to the Holocaust, in which six million Jews and other minorities were systematically murdered from 1939–1945.
Completing this unit should take you approximately 4 hours.
Upon successful completion of this unit, you will be able to:
- discuss the causes of World War II as well as the motivations of the combatants;
- describe the fighting that took place, with special attention to the different places where the war was fought; and
- analyze the post-war consequences of World War II and how they reshaped Europe and the world.
12.1: The Lead-Up to World War II, an Unstable Peace
The division of Europe into nation-states, German anger over the harsh terms of the Treaty of Versailles, and the economic disorder of the 1930s all helped to make another conflict possible. Nonetheless, it did not happen immediately. Germany needed time to rearm, and Britain and France hoped they could restrain Hitler through good diplomacy. Meanwhile, Japan embarked on aggressive expansion in Asia, which angered and worried the United States.
Read this text on Hitler's increasingly aggressive provocations in Europe, which led to World War II. Britain and France responded immediately to Hitler's invasion of Poland on Sept. 1, 1939, with declarations of war. The United States followed two years after its attempts to remain neutral became untenable when Japan attacked the United States at Pearl Harbor on Dec. 7, 1941.
Watch this video for an overview of the prelude to World War II.
12.2: Theaters of War, World War II
World War II was a global conflict, though certain areas were central to the fighting. Eastern Europe, North Africa, East Asia, and Oceania were all pivotal battlegrounds. Even in the United States, where German and Japanese bombers could not attack, Americans could watch as their ships were torpedoed by German submarines in 1942.
Read this text on the Allied and Axis operations in Europe, Africa, East Asia, and the Pacific during World War II. Why are the Battles of Stalingrad and Midway considered turning points in the war? How did the Holocaust evolve after Germany invaded Poland?
Read this text for an overview of the conflict of World War II.
Hitler's antisemitic beliefs formed a major backbone of the Nazi Party. These policies gradually denied Jewish people their rights as German citizens. The government soon encouraged its paramilitary forces and regular citizens to destroy Jewish businesses (such as during Kristallnacht, the "Night of Broken Glass," in November 1936), forced them to live in ghettos, and eventually transported them to their deaths in forced labor concentration and extermination camps.
Historians estimate the German government killed six million Jews and at least five million prisoners of war during the Holocaust.
Read this discussion of the Holocaust. Pay attention to the roots of antisemitism, which Hitler outlined in his bestselling book Mein Kampf, and how he convinced his enablers to commit such crimes against humanity.Watch this video to learn more about how World War II ended.
12.3: Reconstruction and the Effects of World War II
In the same way that World War I dramatically changed Europe, World War II restructured the rest of the world. Europe was divided. The Soviet Union quickly placed Eastern Europe under the control of local Communist parties aligned with Moscow. The war had shattered European rule in Asia, just as Japan's initial victories broke the myth of European superiority. Meanwhile, Western Europe was economically devastated; even Britain was left nearly bankrupt.
Read this text on the final stages of World War II, the agreements reached in Yalta (February 1945) and Potsdam (July-August 1945), the atomic bomb, and efforts to transform Germany and Japan after their surrender.
Read this text on life at home in several parts of the world during World War II, how the war impacted women's lives, and new technologies that affected its outcome.
The state of the European economy after 1945 was dire. Millions of people faced starvation because they could not get enough food. Many cities were destroyed by fighting and bombing. Even Britain was on the verge of bankruptcy. To guarantee a long-lasting peace, the United States worked with European countries to rebuild them.
World War II led to the creation of the most devastating weapon in human history: the atomic bomb. The bomb had a profound impact on the postwar world. As you read this text, pay attention to its legacy in the section "The Use of the Bombs and the Legacy of the Project."
Read this lesson on the goals and objectives of the Allies.
In 1945, in the wake of the destruction of World War II, the leaders of China, France, Russia, the United Kingdom, and the United States (the U.N. Security Council) met with their counterparts from 22 nations to create the United Nations.
Read this article, which describes the many goals and activities of the United Nations, which include offering international conferences and international observances; promoting arms control and disarmament; human rights, humanitarian assistance, international development, and peacekeeping; helping broker treaties; and helping to enforce international law.
Unit 12 Assessment
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