What was the main cause of World War 2?
Among the causes of World War II were Italian fascism in the 1920s, Japanese militarism and invasion of China in the 1930s, and especially the political takeover in 1933 of Germany by Hitler and his Nazi Party and its aggressive foreign policy.
The realization of German dominance in Europe, its leaders calculated, would require war. After securing the neutrality of the Soviet Union (through the August 1939 German-Soviet Pact of nonaggression), Germany started World War II by invading Poland on September 1, 1939.
- Japan`s attack on Pearl Harbor in 1941 brought the United States into the war on the Allied side. Germany and its six allies were known as the Axis. The Allied and Axis countries circled the globe in World War II.
- The action Japan chose was a surprise attack on the U.S. naval base at Pearl Harbor, Hawaii, on December 7, 1941. This action brought the United States into World War II in both theaters, Europe and the Pacific.
- On October 1, 1938, Adolf Hitler's army marched into the Sudetenland in Czechoslovakia, continuing Nazi Germany's aggressive World War II offensive. The World War II timeline below highlights this event as well as other important events that took place from September 15, 1938, to January 5, 1939.
There was only one event that led the US to enter WWII. That was the Japanese attack on Pearl Harbor in what was then the Territory of Hawaii. That happened on December 7, 1941. No other event actually caused the US to participate in the war.
- The primary events that led to the United States declaration of war against Germany were the Zimmerman Telegram and Germany's announced intention to resume unrestricted submarine warfare. American sentiment had leaned toward the Allies and against the Central powers for some time.
- The Japanese attack had several major aims. First, it intended to destroy important American fleet units, thereby preventing the Pacific Fleet from interfering with Japanese conquest of the Dutch East Indies and Malaya and to enable Japan to conquer Southeast Asia without interference.
- The United States drops an atomic bomb on Hiroshima. The Soviet Union declares war on Japan and invades Manchuria. The United States drops an atomic bomb on Nagasaki. Having agreed in principle to unconditional surrender on August 14, 1945, Japan formally surrenders, ending World War II.
Updated: 26th November 2019