World War II Summary

  • Last updated on November 10, 2022

Although millions of people were forced into mass migration by the war, the U.S. government maintained most of its restrictions on immigration despite a national labor shortage. Presidential executive orders allowed some refugees to enter the United States, and Congress passed some laws allowing limited numbers of wartime refugees, Mexican laborers, and Chinese nationals to enter. After the war ended, the United States admitted substantial numbers of refugees.

Until Japan launched its surprise Pearl Harbor attackattack on Pearl Harbor, the great U.S. naval base in Hawaii, on December 7, 1941, the majority of Americans had wanted their country to stay out of the growing world conflict. The previous decade had been of low, sometimes even negative, immigration into the United States because the entire world was suffering under the Great Depression. Millions of Americans had been unemployed, and immigrants posed the threat of competing with them for scarce jobs. After the United States declared war on Japan, Germany, and Italy immediately after Pearl Harbor, the number of immigrants entering the country fell even lower because transocean shipping was devoted almost entirely to the war effort, and international flights were not available to civilians.Germany;in World War II[World War 02]World War II[World War 02]Japan;in World War II[World War 02]Germany;in World War II[World War 02]World War II[World War 02]Japan;in World War II[World War02][cat]WARS;World War II[cat]REFUGEES AND DISPLACED PERSONS;World War II[cat]PUSH-PULL FACTORS;World War II

Another reason that immigration rates were low was the persistent anti-immigration feelings of substantial portions of the American voters who feared competition from newcomers. Some of this feeling reflected nativist attitudes about the alleged inferiority of peoples from regions other than northern and western Europe, from which most early American immigrants had originated. Most Americans were opposed to lifting national immigration quotas, even as tragic circumstances in Europe were increasing the numbers of homeless refugees. Congressional leaders who wanted to take in more refugees saw their legislative measures fail. Only President Roosevelt, Franklin D.[p]Roosevelt, Franklin D.;and war refugees[war refugees]Franklin D. Roosevelt’s executive orders could open the doors wider for some of the refugees.

Enemy Aliens in the United States

At the moment that the United States entered the war, significant numbers of citizens of the principal enemy nations–Germany, Italy, and Japan–were residing in the United States. Moreover, huge numbers of American citizens traced their ancestry to immigrants from these same nations. Many Americans turned their suspicions on people who were obviously of German, Italian, and Japanese ancestry. However, perhaps because of their more distinctive physical appearance, people of Japanese ancestry were treated most harshly.

During World War II, Asian entrepreneurs such as this Filipino farmer advertised their non-Japanese ethnic identities in order to do business safely.


Indeed, the treatment of Japanese–both Japanese nationals and American citizens–became one of the most shameful episodes in American history. Japanese American internmentMore than 110,000 of these people were taken from their homes on the West Coast and interned in bleak relocation camps in remote interior regions. About 70,000 of these people were American-born citizens, called Nisei. The rest were first-generation immigrants, called IsseiIssei, who had been barred from American citizenship, along with other Asians, by federal immigration laws. Public and government fear that these people might be disloyal to the United States by collaborating with a rumored Japanese invasion of the West Coast prompted the internments. Ironically, although the Hawaii;in World War II[World War II]Hawaiian Islands, which were home to more than 200,000 persons of Japanese heritage, were a much more likely target for Japanese invasion than the U.S. mainland, they were not affected by the internment order. Because the islands’ Japanese residents constituted about one-half the territory’s entire population, interning them would have brought economic chaos.

Despite the federal governments’ harsh treatment of Japanese residents, thousands of Nisei–many from the internment camps–patriotically volunteered for military service and formed one of the most decorated combat units in the U.S. Army during the war. Others served in the Pacific theater of the war as translators. Some left the camps to work in factories. Although the internment program disrupted the lives of the internees and caused many of them to lose their homes and businesses, it helped to disperse the Japanese community geographically and introduce them to many economic opportunities outside their traditional work in agriculture.

Members of other alien communities within the United States were treated less harshly. When the war began, at least 1 million enemy aliens were living in the United States, and millions more people from Italian immigrants;and World War II[World War 02]German immigrants;and World War II[World War 02]Germany and Italy were naturalized citizens. Of these people, only a few thousand German and Italian nationals and an even smaller number of naturalized citizens from enemy nations were deemed sufficiently dangerous to require internment during the war. Most were held in camps in North Dakota;wartime internment campsNorth Dakota and Montana;wartime internment campsMontana. Before the war was over, President Roosevelt canceled the designation of enemy aliens for Italians in the United States.

Wartime and Postwar Mass Migrations

Wartime migration within the United States involved internal population shifts rather than waves of immigration. Fifteen million Americans left their homes for military training, and three-quarters of them went overseas. One in five Americans migrated during the war, and 8 million of them became permanent residents in other states. The main flows were toward West and East Coast defense industries and factories in the upper Midwest. In contrast, the rural South and Midwest saw sharp population declines. Most notably, African Americans;and World War II[World War II]African American migrants left the South in large numbers in order to work on jobs under federal contracts in northern factories that required equal wages and fair treatment. ManyPuerto Rican immigrants;and World War II[World War II]Puerto Ricans came to the mainland and many Native Americans left their reservations in order to work in wartime industries.

In contrast, migrations within Europe were brought on by a series of catastrophes. When German armies advanced to the east, millions of German settlers followed them. When the Soviet armies countered from the east, ethnic Germans from all over eastern Europe fled westward. Throughout the war, Germany conscripted workers in conquered areas and moved them about. After the war ended, these people swarmed through Central Europe seeking passage home. Large numbers of surviving prisoners of war were similarly on the move. During the early stages of the war, Holocaust;survivorsJews fled from German domains–many to Palestine in the Middle East. By the end of the war, not many of Europe’s Jewish peoples were left alive, and only a remnant were on the move. At the war’s end, Central Europe resembled an anthill that had been kicked.

Special Categories of Wartime Immigrants

The term “displaced persons,” or DPs, was applied to people driven out of their countries by war. The total number of persons displaced by World War II may never be known, but estimates have ranged from 8 to 20 million. By 1945, only a few thousand displaced persons had been admitted to the United States. President Truman, Harry S.[p]Truman, Harry S.;and displaced persons[displaced persons]Harry S. Truman issued a directive to admit more, and his order was followed by Congress’s [a]Displaced Persons Act of 1948Displaced Persons Act of 1948, which eventually allowed 400,000 war refugees to immigrate to the United States directly from the camps in which they were temporarily residing. Until then, U.S. law did not officially recognize refugees as an immigrant category and had no provisions for offering them asylum.

German German immigrants;scientistsScientists;German immigrantsscientists constituted another special category of wartime immigrants, and many of them were admitted to the United States after the war ended. Operation PaperclipOperation Paperclip slipped hundreds of German scientists and their families out of Germany and into the United States. Germany’s rocket scientist Braun, Wernher vonWernher von Braun became the most famous of these when he later played a major role in the American space program.

Another special category comprised tens of thousands of War brideswar brides, war fiancés, their babies, and a few war husbands. All of these individuals had become attached to American military personnel serving overseas. Most came from Britain, but many were of French, Italian, Dutch, Australian, and New Zealand origin. After the war, German and Japanese nationals joined this category. Under the provisions of the War Brides Act of 1945, national quotas did not apply to spouses of American military personnel.

Refugees and Displaced Persons

Europe’s largest prewar concentrations of Jewish populations were in Nazi-occupied eastern Europe, especially in Poland and Russia. Not many survived the Nazi death camps to which Jews from all over Europe were sent. Their victims included German Jews who had held the false hope that the Nazis would become more civilized after spending some time in power. The mass Genocide;Jewishgenocide against Jews and other minorities is known as the HolocaustHolocaust. However, despite evidence, most Americans during the war did not believe what was going on, treating information as mere rumors.

Jewish refugees from the Holocaust posed a moral dilemma for Americans before, during, and after the war. The failure of the United States to grant them Asylum, political;Holocaust refugeesasylum in their time of greatest need has been a matter of controversy ever since. Between 1945 and 1950, the United States finally admitted 700,000 refugees, many of them Jewish, but by then the war and Germany’s mass slaughter of Jews were over. Adolf Hitler Germany;Nazi regimeHitler, Adolf[p]Hitler, Adolf;Jewish persecutionhad come to power in 1933, and through the following years, his Nazi regime was an escalating campaign against Jews. Discriminatory laws placed ever greater restrictions on the Jews, and violence was increasingly used against them. Soon, those who sought to flee could not take their money out of the country. Immigration to the United States was problematical because there was a prohibition against immigrants regarded as likely to become public charges.

The number of German Jews who were admitted to the United States in 1936-1937 was small. President Roosevelt, Franklin D.[p]Roosevelt, Franklin D.;and Jewish refugees[Jewish refugees]Franklin D. Roosevelt stretched the limits of his presidential authority to allow some German and Austrian Jews to come. About 50,000 did so before the European war broke out. He also allowed the visas of German and Austrian Jews who were already resident in the United States to be extended. During the war, President Roosevelt ordered the U.S. State Department to issue visas to individual European refugees deemed especially important, such as Einstein, AlbertAlbert Einstein, Fermi, EnricoEnrico Fermi, Mann, ThomasThomas Mann, and Chagal, MarcMarc Chagall. A dozen of these people had already received Nobel Prizes, and most of them made significant contributions to scientific research and the arts in the United States.

In 1944, President Roosevelt established the War Refugee Board, U.S.War Refugee Board that eventually allowed some thousands of rescued refugees to enter the country under his presidential executive orders. Many of the immigrants who came under this arrangement were from the middle class with experience in business and the professions. They generally prospered after arriving in the United States.

Other Wartime Migrants

World War II substantially increased Mexican immigration to the United States because of the nationwide shortage of workers. In 1942, the United States and Mexico formed an agreement to create the Bracero programbracero program, which brought temporary Mexican contract workers into the United States. Many of these workers did not return, and other Mexican immigrants came into the United States on their own. Most Mexican immigrants worked in agriculture in the Southwest; others worked on railroad maintenance. By the end of the war, they were beginning to relocate to other parts of the country.

World War II also brought a significant change for Chinese immigration to the United States. The Chinese Exclusion Act of 1882 was repealed by a new act of 1943. For the first time, the United States allowed a small number of Chinese to naturalize and become citizens. This change was in recognition of China’s role as an important wartime ally.Germany;in World War II[World War 02]World War II[World War 02]Japan;in World War II[World War 02]

Further Reading
  • Divine, Robert A. The Reluctant Belligerent: American Entry into World War II. 2d ed. New York: John Wiley & Sons, 1979. Valuable source of information about the political climate in the United States at the dawn of World War II.
  • Gamboa, Erasmo. Mexican Labor and World War II: Braceros in the Pacific Northwest, 1942-1947. Austin: University of Texas Press, 1990. Detailed history of the life, conditions, and social policy affecting Mexican guest workers who began coming to the United States early during World War II.
  • Gilbert, Martin. The Holocaust: A History of the Jews of Europe During the Second World War. New York: Henry Holt, 1985. Study of the European Holocaust that places U.S. immigration policies in the context of a tragic history.
  • Kennedy, David M. Freedom from Fear: The American People in Depression and War, 1929-1945. New York: Oxford University Press, 1999. Describes how Americans responded to the deprivations of the Great Depression, the recovery period of the New Deal, and the country’s entrance into World War II. Considers immigration issues within the broader context of the war.
  • Ng, Wendy. Japanese American Internment During World War II: A History and Reference Guide. Westport, Conn.: Greenwood Press, 2002. Comprehensive reference source on all aspects of the internment of Japanese people during World War II. Includes a selection of primary documents.
  • Shukert, Elfrieda Berthiaume, and Barbara Smith Scibetta. War Brides of World War II. Novato, Calif.: Presidio Press, 1988. Comprehensive study of war brides that includes many interviews with brides.

Bracero program

Displaced Persons Act of 1948

German immigrants

History of immigration after 1891


Japanese American internment

Jewish immigrants

Prisoners of war in the United States

War brides

War Brides Act of 1945

World War I

Categories: History