The Immigration and Nationality Act of 1965, also known as the Hart–Celler Act and more recently as the 1965 Immigration Act, is a federal law passed by the 89th United States Congress and signed into law by President Lyndon B. Johnson. The law abolished the National Origins Formula, which had been the basis of U.S. immigration policy since the 1920s. The act removed de facto discrimination against Southern and Eastern Europeans and Asians, as well as other non-Western and Northern European ethnic groups from American immigration policy. The National Origins Formula had been established in the 1920s to preserve American homogeneity by promoting immigration from Western and Northern Europe. During the 1960s, at the height of the civil rights movement, this approach increasingly came under attack for being racially discriminatory. With the support of the Johnson administration, Senator Philip Hart and Congressman Emanuel Celler introduced a bill to repeal the formula. The bill received wide support from both northern Democratic and Republican members of Congress, but strong opposition mostly from Southern Democrats, the latter mostly voting Nay or Not Voting. President Johnson signed the Immigration and Nationality Act of 1965 into law on October 3, 1965. In opening entry to the U.S. to immigrants other than Northwestern Europeans, the Act significantly altered immigration demographics in the country for the first time since it was founded. The Immigration and Nationality Act of 1965 created a seven-category preference system that gives priority to relatives and children of U.S. citizens and legal permanent residents, professionals and other individuals with specialized skills, and refugees. The act also set a numerical limit on immigration (120,000 per annum) from the Western Hemisphere for the first time in U.S. history. While proponents of the bill had argued that it would not have a significant effect on the total level of immigration or the demographic mix of the country, it nevertheless increased the total number of immigrants as well as the share of immigrants from Asia and Africa, as well as Eastern and Southern Europe in the following decades. Background The Immigration and Nationality Act of 1965 marked a radical break from U.S. immigration policies of the past. Since Congress restricted naturalized citizenship to "white persons" in 1790, laws restricted immigration from Asia and Africa, and gave preference to Northern and Western Europeans over Southern and Eastern Europeans. During this time, most of those immigrating to the U.S.