How did the U.S. control immigration in the 1920s?

In the 1920s, the U.S. implemented restrictive Immigration policies primarily through the Emergency Quota Act of 1921 and the Immigration Act of 1924. These laws established quotas that limited the number of immigrants from specific countries, favoring northern and western European nations while severely restricting those from southern and eastern Europe, as well as Asia. The legislation reflected the era's nativist sentiment and aimed to preserve the perceived cultural homogeneity of the U.S. population. Overall, these measures significantly reduced immigration levels and shaped the demographic landscape of the country.