Final answer:
Nativism and the Red Scare contributed to the push for immigration restriction in the 1920s in the United States. These sentiments led to the passage of laws that limited immigration based on nationality and significantly reduced the number of immigrants from southern and eastern European countries.
Step-by-step explanation:
Nativism, the Red Scare, and xenophobia all played significant roles in the movement for immigration restriction in the United States during the 1920s. Nativist groups like the American Protective Association fueled anti-immigrant sentiment by promoting discriminatory attitudes towards Jewish and Catholic immigrants. The Immigration Restriction League pushed for mandatory literacy tests, targeting immigrants from non-English speaking countries. These nativist sentiments and fears of radicalism led to the passage of the Emergency Quota Act of 1921 and the Immigration Act of 1924, which restricted immigration based on nationality and significantly reduced the number of southern and eastern European immigrants.