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Japan used the name Greater East Asia War (大東亜戦争, Dai Tō-A Sensō?), as chosen by a cabinet decision on 10 December 1941, to refer to both the war with the Western Allies and the ongoing war in China. This name was released to the public on 12 December, with an explanation that it involved Asian nations achieving their independence from the Western powers through armed forces of the Greater East Asia Co-Prosperity Sphere. Japanese officials integrated what they called the Japan–China Incident (日支事変, Nisshi Jihen?) into the Greater East Asia War.

When did Japan adobt the name for the war?
10 December 1941