The Immigration and Nationality Act of 1965, also known as the Hart–Celler Act >>The act removed de facto discrimination against Southern and Eastern Europeans, Asians, and other non-Northwestern European ethnic groups from American immigration policy. The '65 immigration act abolished the National Origins Formula >>The National Origins Formula had been established in the 1920s to preserve American homogeneity by promoting immigration from Northwestern Europe. >>The National Origins Formula was an American system of immigration quotas, used between 1921 and 1965, which restricted immigration on the basis of existing proportions of the population. It aimed to reduce the overall number of unskilled immigrants (especially from Southern Europe, Eastern Europe and Asia), to allow families to re-unite, and to prevent immigration from changing the ethnic distribution of the largely Protestant population of Northwestern European Americans.