Canada Declares War on Japan Summary

  • Last updated on November 10, 2022

The Japanese attack on Pearl Harbor prompted the Liberal government of William Lyon Mackenzie King to declare war on Japan. Canada’s war effort in Europe overshadowed Canada’s war effort in the Pacific, which was relatively limited. The declaration of war, however, led to the more significant internment of Japanese Canadians for the duration of World War II.

Summary of Event

Canada’s involvement in World War II began on September 10, 1939, when Parliament officially declared war against Germany. For the next two years, the government of William Lyon Mackenzie King paid little attention to events in Asia. This was partly due to a lack of intelligence and diplomatic resources in the region, which forced the Canadian government to rely on information supplied to it by Great Britain and America. It was also due to the central focus that the government placed on the war’s European theater. World War II (1939-1945)[World War 02];Pacific theater World War II (1939-1945)[World War 02];Canadian involvement Canada;declaration of war on Japan [kw]Canada Declares War on Japan (Dec. 7, 1941) [kw]War on Japan, Canada Declares (Dec. 7, 1941) [kw]Japan, Canada Declares War on (Dec. 7, 1941) World War II (1939-1945)[World War 02];Pacific theater World War II (1939-1945)[World War 02];Canadian involvement Canada;declaration of war on Japan [g]North America;Dec. 7, 1941: Canada Declares War on Japan[00360] [g]Canada;Dec. 7, 1941: Canada Declares War on Japan[00360] [c]Diplomacy and international relations;Dec. 7, 1941: Canada Declares War on Japan[00360] [c]Wars, uprisings, and civil unrest;Dec. 7, 1941: Canada Declares War on Japan[00360] [c]World War II;Dec. 7, 1941: Canada Declares War on Japan[00360] King, William Lyon Mackenzie Roosevelt, Franklin D. [p]Roosevelt, Franklin D.;World War II diplomacy[World War 02 diplomacy]

Prior to the Japanese attack on Pearl Harbor in December, 1941, the British formally requested a Canadian brigade for the defense of the island colony of Hong Kong. King and his government agreed and sent a small force of 1,975 poorly trained troops to help defend Hong Kong from a possible Japanese attack. Ottawa had opted to send this contingent not because of any profound link with Hong Kong Hong Kong, Battle of (1941) or desire to bolster British defenses in Asia, but mainly because of domestic political accusations that it was not doing enough in the war. The decision proved to inaugurate one of the blackest periods for the Canadian military during the war.

The Canadian units arrived at Hong Kong on November 16, 1941. On December 7, Canada declared war on Japan in response to the attack on Pearl Harbor. The declaration was confirmed by a proclamation of the king of Great Britain on December 8. At this point, the vehicles and heavy equipment of the Canadian units sent to Hong Kong were still in transit. The war in the Pacific prevented the equipment from ever reaching the Canadian soldiers. Moreover, the British underestimated the Japanese threat, believing it could easily be repelled. On December 8, the Japanese attacked swiftly and breached the British defenses on the Chinese mainland that bordered the island. On December 18, the Japanese launched an amphibious assault on Hong Kong.

Horribly outnumbered, poorly equipped, and suffering shortages of water, food, and medicines, the Canadians managed to mount a fierce defense before being pushed back. Over the following week, the remaining Canadian and British forces launched repeated counter-attacks, but to no avail. On Christmas Eve, the British Command ordered the troops to surrender. The captured prisoners were treated brutally. A total of 128 Canadian prisoners of war died at Hong Kong of disease, starvation, and harsh maltreatment by the Japanese. Of the 1,975 Canadians who arrived in Hong Kong, a few more than 1,400 lived to make it home.

The attack on Pearl Harbor, followed by the defeat at Hong Kong, had dire consequences for Canadians at home. Anti-Asian sentiment had increased throughout Canada in the 1930’s, especially in British Columbia, where the majority of Canada’s Asian community lived. The Japanese Canadian community faced the brunt of racial hostility Racial and ethnic discrimination;Japanese Canadians that was fueled partly by Japanese militarism and partly by a predictable anxiety over culturally and racially different peoples immigrating to a nation with a relatively homogeneous population. The tensions that had built during the 1930’s were exacerbated by the advent of war with Japan, and they were further exacerbated by the fall of Hong Kong just weeks later. These tensions were expressed in increasingly shrill expressions of concern over the possible invasion of the Canadian West Coast by Japan.

The small community of Japanese Canadians bore the brunt of these fears. Fueled by racist agitators, the public, particularly in British Columbia, demanded that Ottawa move against Japanese Canadians living in British Columbia, fearing that the community might act as a fifth column. While King believed that Japan might attack Alaska and British Columbia, his government appeared confident that no immediate threat existed from Japanese forces. This was a view supported by the army and the police, but it did little to dissipate the public outcry. Many politicians in British Columbia became hysterical in their demands that something be done about the “threat.” In particular, they demanded the expulsion of the Japanese community.

After demurring for weeks, the King government acquiesced and announced in January, 1942, its plans to remove Japanese nationals from the West Coast. On February 24, Ottawa introduced legislation that permitted the evacuation of all persons of Japanese ancestry from the West Coast. Some twenty-two thousand Japanese Canadians living in coastal British Columbia, including women and children, were soon moved to camps Internment camps, Canadian Japanese Canadians, internment of Canada;Japanese internment in the interior of British Columbia. Several hundred males deemed “dangerous” were placed under armed guard at an isolated camp in Ontario.

Those interned had their property confiscated and sold at bargain prices, and thus at a considerable economic loss to the owners. About one thousand Japanese evacuees labored on sugar-beet farms in Alberta and Manitoba, taking on a job that most German prisoners of war interned in Canada, let alone free Canadian citizens, refused to do. After the war, Ottawa resettled the Japanese Canadians across Canada and even attempted to deport thousands, many of whom were Canadian citizens, to Japan. Although the federal government abandoned these plans in 1947, hundreds of Japanese Canadians, embittered by life in Canada, chose to emigrate to Japan.

After the disaster at Hong Kong, King was cautious about making further defensive commitments in the Pacific theater. Like Canada, Australia was a member of the British Commonwealth, and both nations had historic ties through this mutual link. Unlike Canada, however, Australia’s government believed that Japanese forces would invade Australia by May, 1942. In February, the Japanese bombed the northern Australian city of Darwin and captured Singapore, the largest British military base in Asia. These events inflated Australian fears, and Canberra asked for Ottawa’s help. King demurred, citing military commitments to the European theater, which were significant, and domestic concerns in Quebec about conscription. King’s was not a heroic decision, but it was the right strategic choice for Canada, given the uncertainty of Japanese plans in the North Pacific—not to mention the enormous logistical complications of sending and supplying Canadian forces across the breadth of the Pacific Ocean. However, the Canadian decision-making process was languid, making Ottawa appear indifferent to Australia’s plight.

Canada’s ambiguous policies toward the war in the Pacific were also evident during the Japanese invasion of the Aleutian Islands of Alaska. In the spring of 1942, the Japanese occupied the islands of Attu and Kiska, and American military officials sought two Royal Canadian Air Force squads to help shore up American defenses. U.S. president Franklin D. Roosevelt discussed Alaska’s vulnerability with King and sought Canada’s support. This request was supported by some of King’s principal advisers, who advised that Canada’s war effort need not solely be directed against Germany. King conceded, and Canada’s military presence in the Aleutian campaign expanded to a meager five naval vessels; three small anti-aircraft batteries were despatched.

In May, 1943, the Canadian government also agreed, after considerable debate, to send an infantry brigade group to Kiska. In the end, it was all for naught. On August 15, 1943, Canadian and American forces landed on Kiska, but the Japanese had already secretly withdrawn. Some of King’s senior generals and diplomats advocated that Canada expand its military role in the North Pacific, but King rebuked them as he grew concerned that Canada would be unable to meet its future commitments in the Pacific as the Canadian military became heavily engaged in Europe.

By the end of 1943, Canada’s limited North Pacific operations had ended, and Canada’s military focused on European operations. Still, King acknowledged that Canada was obligated to play some further role in defeating Japan: He merely wanted it to be the “right one.” Despite this nebulous desire, no further Canadian military or naval units saw combat in the Pacific. The year 1943 marked the end of the Canadian war in that theater.


An assessment of the Canadian war effort against Japan illustrates Canada’s ambiguous views and unease toward events in Asia and the Pacific during this period. Canada’s Pacific military efforts were often indecisive and politically expedient, designed merely to show that Ottawa had some stake in the Pacific theater. The decision hastily to send troops to Hong Kong was a poor one and stands as an example of political expediency trumping good military decision-making. The result was tragic, and the King government appeared haunted by its decision. This was reflected in the excessive caution King demonstrated in his decisions regarding Australia and the Aleutians.

The question of how and where Canadian forces could best be used in the Pacific once war in Europe concluded lingered. At home, the reactions to Pearl Harbor and the defeat at Hong Kong revealed the depth of long-standing racist sentiments on Canada’s West Coast. Ottawa’s willingness quickly and ingloriously to evacuate the Japanese Canadians provides a fine example of how susceptible governments can be during times of crisis to rash public opinion. The decision also reflected King’s political sensibilities to maintain national unity and order. In September, 1988, the Canadian government officially apologized for its internment of Japanese Canadians and offered compensation to those members of the Japanese Canadian community affected by the wartime evacuation. World War II (1939-1945)[World War 02];Pacific theater World War II (1939-1945)[World War 02];Canadian involvement Canada;declaration of war on Japan

Further Reading
  • citation-type="booksimple"

    xlink:type="simple">Bangarth, Stephanie. “Mackenzie King and Japanese Canadians.” In Mackenzie King: Citizenship and Community, edited by John English, Kenneth McLaughlin, and P. Whitney Lackenbauer. Toronto, Ont.: Robin Brass Studio, 2002. An insightful evaluation of King’s attitudes and actions toward Japanese Canadians during World War II.
  • citation-type="booksimple"

    xlink:type="simple">Granatstein, J. L. Canada’s Army: Waging War and Keeping the Peace. Toronto, Ont.: University of Toronto Press, 2002. A general survey of Canadian military history since 1867. Provides an excellent starting point for the study of Canadian military history.
  • citation-type="booksimple"

    xlink:type="simple">Perras, Galen. “No Need to Send an Army Across the Pacific: Mackenzie King and the Pacific Conflict, 1939-1945.” In Mackenzie King: Citizenship and Community, edited by John English, Kenneth McLaughlin, and P. Whitney Lackenbauer. Toronto, Ont.: Robin Brass Studio, 2002. Based on declassified materials, this is one of the best studies of King’s perspective and policies toward the Pacific theater.
  • citation-type="booksimple"

    xlink:type="simple">Roy, Patricia, et al. Mutual Hostages: Canadians and Japanese During the Second World War. Toronto, Ont.: University of Toronto Press, 1990. Many Canadian historians argue that Canada’s wartime policies toward the Japanese in Canada were motivated by long-standing racial hostility. This study provides a more sympathetic approach, suggesting that Ottawa carried out the evacuation of Japanese Canadians for their own protection, as well as out of genuine national security concerns.

World War II: Pacific Theater

World War II: European Theater

Bombing of Pearl Harbor

Japan Begins Attacks on Southeast Asia

Churchill Visits Canada as World War II Ally

United States Interns Japanese Americans

Central Pacific Offensive

Canada Implements Conscription After Months of Crisis

Canada’s Citizenship Act Is Passed

Categories: History