Immigration during WWII

The cataclysm of World War II (1937–45) had a profound effect on immigration to North America. With restrictive immigration policies in place by the 1920s, interwar immigration to the United States and Canada had been dramatically curtailed from the peak years just before World War I (1914–18; see World War I and immigration). The exigencies of war dropped the numbers further still. The United States admitted almost 1.3 million immigrants in 1907, 50,000 in 1937 when war broke out in China, and less than 24,000 in 1943. Canada’s peak year had been 1913, when almost 400,000 immigrants landed; immigration in 1937 dropped to about 12,000 and further down to 7,445 in the trough year of 1943. But war also changed people’s attitudes toward immigrants and those who might become immigrants and presented enormous challenges to current policies. First raised were security questions regarding potential enemies: What should be done with the millions of Japanese, Germans, and Italians living in North America? Also, with millions of men and women serving abroad, labor needs had to be met at home, and provision had to be made for foreign families acquired while overseas. Finally, there were humanitarian questions regarding the protection of children threatened by war and the eventual resettlement of refugees and other persons displaced by the war. As a result of these challenges, a number of important exceptions were made to the various immigration restrictions in the United States and Canada. Anti-Catholicism and anti-Semitism declined in the United States, and there was a generally less hostile attitude toward nonfounding ethnic groups throughout North America. Though major new immigration legislation was not passed, changing attitudes as a result of the war did pave the way for more far-reaching legislative changes in the future.
http://immigrationtous.net/319-world-war-ii-and-immigration.html
https://www.ushmm.org/wlc/en/article.php?ModuleId=10007094