Immigration to the U.S. as a whole, however, remains complicated.
Prior to 1965, immigration to the U.S. was most feasible for individuals from Northern and Western Europe, while there were heavy restrictions and bans on immigration from Asia.
The 1965 Immigration and Nationality Act shifted that paradigm, opening up immigration from South America and Asia. The Immigration Act of 1990 continued that trend, allowing legal immigration from more countries across the globe.
Since the passage of the 1965 Immigration and Nationality Act, around 72 million individuals have immigrated to the U.S.