Non-US citizens may be declared an Honorary Citizen of the United States by the President following an Act of Congress. As at May 23, 2002 five people had had this honour bestowed upon them.
... (died 1997), French marine biologist and explorer
Alexandra David-Néel, (1868-1969), French explorer, visited Lhasa, Tibet in 1924
Cavalier de la Salle[?], ...