''Citizen of the Galaxy'' is a science fiction novel by Creator/RobertAHeinlein first published as a serial in 1957.

For as long as Thorby can remember, he's been a slave, futilely resisting as he was sold to a succession of masters. Now, in the slave markets of the space port of Jubbulpore (capital of the Nine Worlds), he's bought by the beggar Baslim the Cripple, for the token sum of nine minims. Thorby eventually learns that Baslim is far more than he appears, as the old man teaches him lessons about how to both think and live as a free man, while enlisting his help in spying on the ships arriving at the port.

When Baslim is hunted down and killed as a spy, Thorby is forced to obey the last request of his Pop and escape on one of the ships of the Free Traders, a insular yet ProudMerchantRace who owe a debt to Baslim that can't be repaid -- although adopting Thorby would be a good start.

So Thorby begins a journey that takes him from one end of the galaxy to the other, and his journey that started with him in the depths of slavery catapults him to the highest levels of society. And at every step, he has to struggle with the nature of freedom and how he can find it in his circumstances, even while fulfilling his responsibilities.

!!This novel provides examples of:
* ActualPacifist: Thorby's grandparents are convinced that there is never any reason to resort to violence, even in self-defense. Within the context of the novel, they are shown to be naively misguided as to the way things work outside the Solar System.
* AllMenArePerverts: The Executive Officer of ''Sisu'' confiscates pornographic images from the bachelor's quarters, saying that such filth doesn't belong on their ship. In a bit of ValuesDissonance, the images are implied to be no worse than pinup girls, which would have been risque when the novel was written, but tame by today's standards.
** MarsNeedsWomen: The raid happens while ''Sisu'' is on the planet of StarfishAliens where they have to trade by silent auction because of no common language. The ship's supercargo decides to put the confiscated smut out with the rest of their trade goods instead of having it incinerated. The response is immediate, and the aliens eventually work out an exchange rate of one carved jewel per individual page. The bachelors of the ''Sisu'' swiftly offer their remaining {{Porn Stash}}es for the common good.
* {{Auction}}: This is where the novel opens, as Thorby is put up for sale. The novel's first line: "'Lot ninety-seven,' the auctioneer announced. 'A boy.'"
* AuthorCatchphrase: Characters saying "So?", meaning in the sense of "Is that so?" in context. Several of Heinlein's other works using the phrase are on the trope page.
* BlackMarket: The spaceport area of the city of Jubbulpore:
-->''"The inhabitants brag that within a li of the pylon at the spaceport end of the Avenue of Nine anything in the explored universe can be had by a man with cash, from a starship to ten grains of stardust, from the ruin of a reputation to the robes of a senator with the senator inside."''
* ChasteHero: As usual for a Heinlein juvenile-novel hero, Thorby has a gift for [[ObliviousToLove missing other characters' romantic overtures]], even after still other characters try to explain it to him. He's still not above feeling pleasantly embarrassed by some engineered romantic moments, and does show symptoms of TheDulcineaEffect when the situation seems to warrant it.
* CoolOldGuy: Baslim the Cripple [[spoiler: AKA Colonel Richard Baslim.]]
* CunningLinguist: Thorby knows a smattering of several languages when Baslim buys him, and he learns two or three more throughout the course of the novel. It's implied that Baslim knew even more.
* DeadlyEuphemism: On Jubbulpore, "shortened" is slang for "beheaded".
* DeathByOriginStory: Thorby's parents. Getting them declared legally dead provides the main thrust for the last part of the novel.
* DecidedByOneVote: A slightly more realistic, if no less dramatic, version. Thorby's cousin Leda announces at the very last moment that she, and the thousands of shares in stock she holds, is voting for Thorby.
* DeliberateValuesDissonance: Inherent in the nature of the book itself, which is something of a meditation on how the idea of "freedom" can mean different things to different societies.
* DueToTheDead: During the Free Traders' gathering, Krausa risks missing a memorial ceremony for both his late mother and Baslim in order to bring Thorby to a Terran Guard base and honor Baslim's last wishes. As soon as the base commander discovers that Krausa is about to miss the ceremony, he orders the Free Trader captain to be driven back to the Gathering using a fast air car.
* EvilUncle: Weemsby asks Thorby to call him Uncle John even though they're not actually related (he's the stepfather of a cousin of Thorby's, as well as an old family friend). He's also more ambitious than actually evil, but then, AmbitionIsEvil.
* ExactWords: Thorby's first experience on the ''Sisu'' is as a "fraki" who is literally ignored by the crew to the best of their ability -- until the Chief Officer of the ship, Captain Krausa's mother and superior officer, hears the message Baslim left for the ''Sisu'' and concludes that Baslim's request to care for Thorby "as if you were I" means that Krausa must adopt the boy himself.
* FailedASpotCheck: A sergeant of the guard has a conversation with a fortune teller about how he is searching for Thorby, while Thorby is standing mere feet away pretending to be changing the letters on a theater marquee (although to be fair, Thorby is currently standing on a ladder with his head masked by the glare of the lights, so the only thing the guardsmen could see would be his feet) It's also entirely possible the guy knew it was Thorby, and was trying to subtly tell him to run as far and fast as he can.
* FantasticRacism: Like any clannish society, the Free Traders (or the People, as they call themselves) consider everyone else beneath them. Interestingly, they don't differentiate between humans and aliens: if you're not People, you're nobody. Captain Krausa of ''Sisu'' (and possibly other ship captains) is a bit looser about this, probably because he is often in direct contact with outsiders.
* FishOutOfWater: Thorby constantly passes from one society to the next and has to learn an entirely new set of social mores each time.
* HandicappedBadass: Baslim the Cripple sees and does a lot for a guy who's missing a leg and an eye. [[spoiler: He has prosthetics, but he only uses them when passing himself off as a wealthy citizen.]]
* HeroOfAnotherStory: Baslim the Cripple is much more than the simple beggar he poses as on Jubbulpore. We get snippets of what he's been up to as the story progresses, but we only see what Thorby witnesses firsthand. [[spoiler:Specifically, Colonel Richard Baslim is an agent sent by the Terran Hegemony to investigate and bring down a pervasive slave trafficking ring that uses Terran shipping companies as fronts for its criminal enterprises. Baslim is also a hero to and honorary member of the Free Traders because he was instrumental in rescuing one of their ships from said slavers.]]
* KangarooCourt: Defied. Weemsby and the judge on his payroll attempt to set one up when Thorby seeks to declare his parents legally dead and set himself up as the rightful heir to their estate, but his savvy and equally underhanded lawyer makes sure the case is handled fairly by filling the courtroom with reporters and high-ranking judges.
* KissingCousins: At the Rudbek estate, "Uncle" John tries to foist Leda on Thorby, and she isn't completely against the idea. Thorby is {{Squick}}ed out at first, until he goes over their lineage in his head and realizes that, at least by Free Trader standards, she's not taboo. He still remains against the idea though, because he intends to stay a ChasteHero and doesn't want to hurt her by being an absentee husband because of the X-Corps.
* KnowNothingKnowItAll: Decibel, the corporal Thorby serves under when he first joins the Hegemony military. He claims that Free Traders are cowards who run from raiders. When Thorby corrects him, and states that he himself blew up a raider when he was a Free Trader, Decibel takes him down to one of the ship's gunners to put him in his place. He is shocked when the man not only confirms Thorby's story, but thanks Decibel for making him aware of such a valuable asset as Thorby's gunnery experience.
* MadeASlave: The story begins with Thorby being sold to Baslim. According to his backstory, Thorby had been sold several times before then. Shortly after buying him, Baslim suspects that Thorby wasn't born a slave, but had been captured by slavers. [[spoiler:Turns out he was right.]]
* {{Mutant}}: Humans have mutated in several different directions since spreading out among the stars. When Baslim first buys Thorby, he thinks the boy is between 10-12 years old, but is unsure since some mutants look like normal humans, but age at different rates. When Baslim is able to determine that Thorby is non-mutated, this causes Baslim to conclude that Thorby is probably from the Terran Hegemony, and possibly even Earth.
** Though, the only example seen is one of the other buyers at the slave auction, a "Syndonian" with PointyEars who finds the auctioneer pointing out Thorby's seemingly "perfect" round ears quite insulting.
* NeuroVault: Before he's killed by the Sargon's forces, Baslim takes the time to hypnotize Thorby to memorize his final report, along with a series of messages to the captains of several Free Trader ships (like the ''Sisu''), in their unique languages, asking them to take Thorby offworld.
* NoodleIncident: Several.
** We never find out the exact details of how Thorby himself became a slave [[spoiler:and how his parents died in the same incident]], although the book drops tantalizing hints that it might have been set up by [[spoiler: profiteers within his parents' company who were benefiting from the slave trade themselves]].
** There are several references to Colonel Baslim's rescue of the ''Hansea'' from slavers, but the subject is a taboo among the People so we never find out exactly what happened.
** When Colonel Brisby, Commanding Officer of a military starship, gets the identification back on his newest recruit, a young ex-slave and ex-Free Trader. Turns out the youngster - our protagonist - went missing after a starship "accident" when he was a baby and is in fact the much-sought-after sole heir to a Galaxy-spanning mercantile empire. After reading the message, Brisby muses "Why do things like this always happen to ''Hydra''?", leaving the reader to wonder just what other adventures the Hegemonic Guard Cruiser ''Hydra'' has been involved in.
* NoSuchAgency: X-Corps - the elite branch of the military that [[spoiler: Baslim]] belonged to.
* NotBloodSiblings: Defied with Mata, Thorby's adopted niece. Although the two grow close after some BelligerentSexualTension during Thorby's training as a fire control officer, she's [[NotBloodSiblings technically part of the same moiety (group of the Sisu's crew treated as blood relations)]]. Mata's brother Jeri acts as a chaperone, but the Sisu's Chief Officer (Thorby's adoptive grandmother) takes swift action to trade her to another Free Trader vessel as soon as possible once Mata asks to be adopted into the other moiety to become a legitimate potential mate. As the sociologist Margaret explains to Thorby as soon as this is explained to him, this form of the incest taboo exists for valid reasons in the culture of the People, and Grandmother did the right thing.
* PassiveAggressiveKombat: The Sisu's crew use both formalized descriptions of their positions (e.g. "Starboard Second Assistant Cook") and overly specific familial relations (e.g. "Cross-Cousin-in-Law by Marriage") to refer to each other, depending on a social situation. The sociologist Margaret Mader explains that the excessive politeness of the ship's society is used as an escape valve to avoid tensions that would otherwise lead them to come to blows: "you could go through a day and not utter a phrase not found in the Laws of Sisu." Thorby briefly tries to put this into practice early in his training as a fire control officer.
* PhotographicMemory: Baslim teaches Thorby this skill through a process he calls "Renshawing," after [[http://en.wikipedia.org/wiki/Samuel_Renshaw Samuel Renshaw]]. This process comes up in a few other Heinlein novels.
* RagsToRiches: Thorby goes back and forth, but goes from being a penniless beggar to a member of the well-off Free Trader ship ''Sisu'', and finally becomes [[spoiler:heir to one of the largest {{MegaCorp}}s in human space]].
* RagsToRoyalty: See above.
* RidiculousFutureInflation: Thorby at one point is given a "megabuck", which is a combination of this and WeWillSpendCreditsInTheFuture. The main Terran denomination is the credit (one credit will buy about five loaves of bread, according to Thorby); 100 dollars is 1 credit, 1,000 credits is 1 supercredit, and 1,000 supercredits is 1 megabuck. In other words, a megabuck is a million credits, or 100 million dollars -- which is still considered a lot of money, but not nearly as much as 100 million would be today.
** And that 'megabuck' is considered to be an amount of money that Thorby, Leda, and several other young rich scions could all blow through in several weeks of holiday amongst the resorts and sports for the superrich... in other words, about a million dollars.
* ScrewTheRulesIHaveMoney / ScrewTheRulesIHaveConnections: Weemsby is used to being able to throw money at his problems, and to use the massive influence of his company if that doesn't work. Unfortunately for him, Thorby has money to burn, too.
* ScrewTheRulesImDoingWhatsRight: Captain Krausa defies the orders of his wife to make sure that Thorby is put on a Hegemony vessel, like Baslim asked him to do.
* SelectiveObliviousness: Most citizens of the Terran Hegemony are shocked and horrified when Thorby tells them he used to be a slave, and disbelieve him. His grandparents especially refuse to believe that slavery exists in the Nine Worlds. And when Thorby argues the point with them, they inform him that they know more about the situation than Thorby does, even though he lived through it, and was unambiguously a slave.
* SlaveLiberation: In the BackStory, Colonel Baslim stormed a raider's compound and freed the crew of a Free Trader starship who had been captured to be made into slaves.
* SpaceCossacks: The play Aunt Athena wrote for the Free Traders' Gathering, [[VeryLooselyBasedOnATrueStory based on]] the origin of the ''Sisu'' itself, portrayed its first captain as a "saint with a heart of steel" who went into space because of his disgust with the "evil ways of fraki". Since the play was portrayed in-universe as [[StylisticSuck a poorly-written]] crowd-pleaser, it's safe to say this trope is how the People think of themselves.
* SpacePeople: The Free Traders live in nomadic clans whose homes are their starships. They are noted for being somewhat disdainful of planet-dwellers, whom they sometimes refer to as "fraki".
* StarfishAliens: While a member of ''Sisu'', Thorby encounters two alien races. The descriptions of the races make it clear they're not remotely humanoid. Their cultures and philosophies are also very alien, to the point that ''Sisu'' doesn't even interact directly with one race.
* UsedFuture: The space port of Jubbulpore and its surroundings have this look. While the Free Traders ship ''Sisu'' isn't a ShinyLookingSpaceships, it is clean and luxuriously outfitted since it is the home of successful merchants. We don't see enough of Earth to really know its state.
* WhatWouldXDo: A Colonel mentions that whenever he's faced with a difficult situation, he always asks himself what his former commander [[spoiler: Col. Baslim]] would do.
* WretchedHive: Jubbulpore, Capitol of the Nine Worlds. Or at least, the area by the spaceport where Thorby spends most of his time.