This map (produced in 1940) shows immigration quotas by country as set by the Immigration Act of 1924.
In 1921, the Emergency Quota Act had limited immigration by setting a limit on the number of people admitted from each country. Three percent of that nationality already living in the United States according to the 1910 census would be allowed entry per year.
The Immigration Act of 1924 further restricted immigration. It established the 1890 census as the new base for determining how many immigrants would be admitted and reduced the percentage admitted to 2 percent. Since the foreign-born population of the United States was much smaller in 1890 than in 1910, immigration was more restricted than it would have been by a simple reduction of the base percentage.
People from the Western Hemisphere were exempt. Fewer southern and eastern Europeans, and more northern and western Europeans, were permitted entry. The annual ceiling was lowered from 387,803 to 186,437 immigrants, and visas with photographs were required.
