Superman was an Undocumented Immigrant.

Henry Jenkins on Superman's Immigrant past: "Superman was created by two Jewish high school students, both immigrants from Eastern Europe, in the 1930s; he has become a key vehicle by which another generation of immigrants seeks to understand their place in American society. If ever there was an illegal alien, it is Kal-El from the planet Krypton whose parents sent him away from his native world in search of a better life, who slipped across the border (via spaceship) in the middle of the night, got adopted by an Anglo family, has had to hide his true identity, but has been deeply dedicated to promoting and defending American values."-- Fusion