Chinese Exclusion Act: The Chinese Exclusion Act was an 1882 law that prohibited the immigration of Chinese laborers to the United States.
Emergency Quota Act of 1921: The Emergency Quota Act of 1921 established numerical limits on immigration based on nationality, setting quotas for each country.
National Origins Act of 1924: The National Origins Act of 1924 further restricted immigration by establishing even stricter quotas based on national origins, favoring Northern European immigrants over Southern and Eastern Europeans.