| 1790 | The federal government requires two years of residency for naturalization |
| 1864 | Congress legalizes the importation of contract laborers |
| 1819 | Congress establishes reporting on immigration |
| 1885 | Congress bans the admission of contract laborers. |
| 1898 | Four month Spanish-American War begins with a naval blockade of Cuba and attacks on the island; ends with Cubas independence and U.S. acquisition of Puerto Rico, Guam. |
| 1948 | The United States admits persons fleeing persecution in their native lands; allowing 205,000 refugees to enter within two years |
| 1952 | Immigration and Nationality Act: individuals of all races eligible for naturalization; reaffirms national origins quota system, limits immigration from Eastern Hemisphere; establishes preferences for skilled workers and relatives of U.S. citizens and permanent resident aliens; and tightens security and screening standards and procedures | |
| 1953 | Congress amends 1948 refugee policy to allow for the admission of 200,000 more refugees | |
| 1980 | The Refugee Act redefines criteria and procedures for admitting refugees |
| 1986 | Immigration Reform and Control Act (IRCA) legalizes illegal aliens residing in the U.S. unlawfully since 1982. |
| 1900 | Congress establishes civil government in Puerto Rico; Jones Act grants U.S. citizenship to island inhabitants; allows travel between mainland and the island without a passport . |
| 1929 | Congress makes annual immigration quotas permanent |
| 1965 | Freedom flight airlifts begin for Cuban refugees assist over 260,000 people over the next eight years. | |
| 1966 | The Cuban Refugee Act permits more than 400,000 people to enter the United States. | |
| 1959 | Fidel Castros Cuban revolution prompts mass exodus of over 200,000 people within three years. | |
| 1961 | The Cuban Refugee Program handles influx of immigrants to Miami; 300,000 relocated across the United States during the next two decades. | |