Parliament adjourned on November 14, 1941, and was not scheduled to return until January 21, 1942.[2] At the urging of the Soviet Union, the United Kingdom declared war on Finland on December 6, 1941.[13] At the UK's urging, the Canadian Cabinet the next day issued a proclamation declaring war on Finland,[13] Hungary, and Romania.[2]

On December 7, 1941 (December 8 in Japan), the Empire of Japan began an undeclared war upon the United Kingdom (invading Hong Kong and Malaya), Canada, and the United States (attacking Pearl Harbor).[3] Mackenzie King and the Cabinet decided to go to war with Japan that evening and issued a proclamation the following day declaring that, as of December 7, a state of war existed between Japan and Canada.[2][3][14] That same day, the US and UK also declared war on the Japanese Empire.[3] These proclamations were presented by Mackenzie King to the House of Commons when parliament returned on January 21, 1942.[2]

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