The Internment of Japanese Americans: A 1940s Wartime Injustice Through Primary Sources

On the morning of December 7, 1941, the world changed for Japanese Americans living along the Pacific Coast. The attack on Pearl Harbor turned a long-standing prejudice into a national emergency. Within months, 120,000 people of Japanese descent—two-thirds of them American-born citizens—would be uprooted from their homes and sent to remote internment camps. A photograph of a young boy, suitcase in hand, waiting with his mother for evacuation to Owens Valley, captured the bewilderment of a community that had committed no crime. A shopkeeper’s sign, reading simply “I am an American,” spoke to the loyalty that could not shield them. This is the story of that evacuation, told through the documents, photographs, and personal records that survive.

What Happened?

The Japanese attack on Pearl Harbor on December 7, 1941, triggered a wave of suspicion against all people of Japanese ancestry. President Franklin D. Roosevelt’s Executive Order 9066, signed on February 19, 1942, authorized the removal of any persons deemed a threat to national security. Though the order did not mention Japanese Americans by name, it was applied almost exclusively to them.

• February 1942: Executive Order 9066 signed, creating military exclusion zones.
• March–May 1942: Civilian exclusion orders posted in West Coast cities, instructing Japanese Americans to report for “evacuation.”
• Mid-1942: Over 110,000 people moved first to temporary assembly centers, then to ten permanent relocation camps in remote interior locations—including Manzanar in California, Heart Mountain in Wyoming, and Tule Lake in California.
• 1943–1945: The War Relocation Authority administered the camps; some 33,000 Nisei (second-generation) served in the U.S. military, including the 442nd Regimental Combat Team, while others remained behind barbed wire.

The evacuation was swift and chaotic. Families had only days to sell or store their property. The Library of Congress’s collection of photographs shows the lines of people waiting for buses, the packed suitcases, and the bare barracks that awaited them.

How It Was Seen at the Time

In 1942, the prevailing official view was that the evacuation was a necessary military measure. The language of the orders used neutral terms like “evacuation” and “relocation,” avoiding the word “internment.” A Civilian Exclusion Order posted in Oakland, California, instructed “all persons of Japanese ancestry” to report for removal. The sign “I am an American” that appeared in a store window was a direct challenge to that classification.

“I am an American.” — Photograph of a sign in a Japanese American shop, taken by a photographer for the War Relocation Authority, 1942.

Many contemporaries, including some journalists, accepted the government’s claim that the evacuation was “for their own protection.” However, others, like the writer and journalist Carey McWilliams, argued that it was a “legalized witch hunt.” The prevailing mood among white Americans was one of fear and suspicion, stoked by the attack on Pearl Harbor and the fear of espionage.

Historical Snapshot

What People Knew at the Time

Eyewitness Accounts

Photographs serve as powerful eyewitness records. The Library of Congress holds images like “Japanese-American child who is being evacuated with his parents to Owens Valley” (February 1942) and “A large sign reading ‘I am an American’” (1942). These images, taken by government photographers, document the moment of uprooting and the quiet dignity of those who obeyed orders. The diary of Stanley Hayami, a high school student incarcerated at Heart Mountain, Wyoming, provides a personal, written record of daily life. In his diary, Hayami describes the cold, the dust, the monotony, and the constant uncertainty about the future. His words, preserved by the Smithsonian, offer a rare first-person glimpse into the camp experience.

Letters & Diaries

The diary of Stanley Hayami is one of the most poignant primary sources. Hayami, a Nisei, was a student at Heart Mountain. He wrote about his hopes, his family, and his longing for a normal life. His diary, now held by the Smithsonian, was published after his death in combat. In one entry, he reflects on the irony of being forced to leave his home while being an American citizen. Though we do not have the exact text here, the diary’s existence and its content have been documented in the primary source set “Japanese American Incarceration Through Primary Sources: The Diary of Stanley Hayami.” The diary is a testament to the personal cost of the injustice.

Daily Life

Life in the camps was harsh. Photographs from the Library of Congress show “Mess line, noon, Manzanar Relocation Center,” “School children, Manzanar,” and “Roy Takeno reading paper in front of office.” The camps were built quickly; families lived in single rooms in tar-papered barracks. Meals were served in communal mess halls, and privacy was scarce. Children attended school in barracks, while adults worked at low-paying jobs within the camp. The government encouraged “self-governance,” but the ultimate authority was the War Relocation Authority. The daily routine revolved around the mess hall, the latrine, and the work assignment. Despite the conditions, many families tried to create a semblance of normalcy—gardens, sports teams, and cultural events. The photograph of the “Mess line, noon, Manzanar” shows a long line of people with trays, waiting for food in a dusty yard.

How Historians See It Today

Modern historians overwhelmingly view the internment as a grave injustice, driven by racial prejudice, war hysteria, and a failure of political leadership. The 1980s report of the Commission on Wartime Relocation and Internment of Civilians concluded that the exclusion was not justified by military necessity. It was a mistake that cost the U.S. government billions in reparations, which were paid to survivors in the 1990s. Contemporary historians also emphasize the distinction between the “internment” of Japanese Americans and the “incarceration” of enemy aliens, and they note the term “concentration camp” is sometimes used to describe the camps, though it differs from the Nazi camps. The primary sources—the photographs, the diaries, the exclusion orders—are now used to teach about the fragility of civil liberties in times of crisis.

The primary sources of the internment—the photographs of children behind barbed wire, the sign that declared “I am an American,” and the diary of a young man who died in combat—remain a powerful reminder of how fear can erode the law. They teach us that the rights we hold are not guaranteed; they must be defended, even against our own government.