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Mass internment of AJAs on Mainland begins


  • Japanese American families depart for internment camp

Executive Order 9066

Executive Order 9066, signed by President Franklin D. Roosevelt on February 19, 1942, authorized what was to become the mass forced removal and incarceration of all Japanese Americans on the West Coast. The order authorized the secretary of war and any military commander designated by him "to prescribe military areas…from which any or all persons may be excluded." The order does not mention Japanese Americans by name. As a result of this order, some 110,000 Japanese Americans living on the West Coast were removed from the West Coast, most to inland concentration camps. Public Law 503, enacted a month later, allowed federal courts to enforce the military orders resulting from EO 9066.

The signing of the order culminated in an internal conflict within the administration between Francis Biddle’s Justice Department on the one hand and Henry Stimson’s War Department and the army on the other. The key proponents of mass exclusion—led by Western Defense Commander John L. DeWitt and army strategist Karl Bendetsen along with Assistant Secretary of War John J. McCloy—eventually won over the president, citing "military necessity" as the core rationale.

The order withstood legal challenge before the Supreme Court, which upheld the constitutionality of the order in the case of Korematsu v. United States. However in the coram nobis cases some forty years later, it was disclosed that government lawyers withheld crucial evidence that disputed the claim of "military necessity."

Executive Order 9066 lapsed at the end of the war and was eventually terminated by Proclamation 4417, signed by President Gerald Ford on February 19, 1976.

Authored by Brian Niiya, Densho

For More Information

Commission on Wartime Relocation and Internment of Civilians. Personal Justice Denied: Report of the Commission on Wartime Relocation and Internment of Civilians.  Washington, DC: U.S. Government Printing Office, 1982. Foreword by Tetsuden Kashima. Seattle: University of Washington Press, 1997.

Daniels, Roger. Prisoners Without Trial: Japanese Americans in World War II. New York: Hill and Wang, 1993.

Executive Order 9066. Accessed at

Irons, Peter. Justice at War: The Story of the Japanese American Internment Cases. New York: Oxford University Press, 1983.

This event article is presented in full from the Densho Encyclopedia

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