Japan during World War II

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Japan participated in World War II from 1939 to 1945 as a member of the Axis. World War II and the Second Sino-Japanese War encapsulate a significant period in the history of the Empire of Japan, marked by significant military campaigns and geopolitical maneuvers across the Asia-Pacific region. Spanning from the early 1930s to 1945, Japan employed expansionist policies and aggressive military actions, including the invasion of the Republic of China, and the annexation of French Indochina.

In 1941, Japan attempted to improve relations with the United States in order to reopen trade, especially for oil, but was rebuffed. On 8 December, 1941, Japan attacked multiple American and British positions in the Pacific. The Pacific War, a major theater of World War II, further intensified Japan's engagements, leading to significant confrontations with Allied forces in the Pacific Ocean and Southeast Asia. Although initially successful, Japan took significant losses at the Battle of Midway. In addition, Japan met significant setbacks in China. On 6 and 9 August, 1945, Japan was hit by two atomic bombs, while the Soviet Union declared war and invaded Manchuria on 8 August. These events led to the surrender of Japan on 15 August.

During the war, the Japanese committed several war crimes, including attacking neutral countries without a prior declaration of war, massacres and rapes of civilians, the use of comfort women, and biological and chemical warfare and experimentation. In addition, prisoners of war were mistreated, executed, and experimented on.