Citizen of the Galaxy is a novel by Robert A. Heinlein, originally serialized in Astounding Science Fiction (September, October, November, December 1957) and published in hardcover in 1957 as one of the Heinlein juveniles by Scribner's. Influenced by Rudyard Kipling's Kim, the novel, like many of Heinlein's, may also have been influenced by the author's background in and nostalgia for the U.S. Navy.