The Immigration and Nationality Act of 1965 abolished the national origins quota system (see also: The Emergency Quota Act, 1921-1924) that had defined U.S. immigration policy since the 1920s. The 1965 Act, also known as the Hart-Celler Act, marked a significant change, replacing the quota system with a preference-based model. It aimed to attract skilled labor and prioritized reuniting immigrant families.
The growing influence of the Civil Rights Movement in the 1960s largely influenced this large-scale immigration reform. Through the movement’s emphasis on equality, the national origins system came to be viewed by many as a discriminatory policy that favored Northern Europeans. As a result of the 1965 Act, 170,000 visas were allotted to immigrants from countries in the Eastern Hemisphere and 120,000 to those from the Western Hemisphere, increasing the annual immigration ceiling from 150,000 to 290,000. The new system sparked a wave of diversified migration from Asia, Latin America, Africa and Europe.