And as often as you reflect how much power you have over a slave, remember that your master has just as much power over you. "But I have no master," you say. You are still young; perhaps you will have one. Do you not know at what age Hecuba entered captivity, or Croesus, or the mother of Darius, or Plato, or Diogenes?
Mahou Sensei Negima! has Ako, Natsumi, and Akira selling themselves into slavery shortly after their arrival in the magic world to pay for a very ill Ako's expensive medicine. Tosaka abuses them on occasion, but their actual owner (a literal Mama Bear who's in charge of a tavern) beats the crap out of him for it. Even then, Tosaka only looks down on them because he was once a slave himself (and so was Mama, who knows him from these days). Negi eventually manages to buy their freedom, and that fires Tosaka's envy since it took him twenty years to buy his own freedom.
Several recent chapters reveal that the reason Jack Rakan is so crazy powerful is because he spent pretty much his whole life fighting as a gladiatorial slave, before winning his freedom and starting to fight in wars.
Recently in Vinland Saga, Thorfinn has become a slave working in Jutland.
In +Anima, all of the four main character's are made into slaves when they go to Sailand. Senri is the only one sold at a slave market though.
Several characters in One Piece on separate occasions. Among them we have Nami, Fisher Tiger and other Fishmen, the Gorgon sisters Hancock, Sandersonia and Marigold, Robin (When she was sent to Tequila Wolf), and even Silvers Rayleigh (Though in his case, it was on purpose so he could steal money from whoever was stupid enough to buy him).
Ayase in Okane Ga Nai gets sold by an unscrupulous cousin to pay that cousin's Yakuza debts.
This almost happens to Kino in Kino's Journey, where Kino helps a group of slavers from a life-threatening situation without knowing their true vocation, and they respond by trying to enslave her, even as they spout praises for her kindness.
Happened to Ciel (and in the anime's second season, Alois) in Black Butler.
Although it's not the mainline slave trade, Wolfwood got adopted under false pretenses and then Strapped to an Operating Table; that they then armed him and sent him out as a professional hitman was kind of their bad judgment, except he never actually did turn on the Eye—just his 'master,' and then only to get a shot at the Omnicidal Maniac they had a contract to.
Everyone involved with building the Tower of Heaven in Fairy Tail.
Many painters depicted such slave markets, usually in Orientalist scenes or ones from ancient Greek or Rome. The Other Wiki has a number here. Also the full Captive Andromache◊
Part of the backstory of Starfire in Teen Titans. Her evil sister betrayed their planet, Tamaran, and helped hostile aliens conquer it, and as part of the terms of their defeat, the Tamaranians were required to surrender Starfire, their princess, into slavery.
In Thundercats - The Return, Lion-O enters a magical book to train, and emerges 10 years later to discover that the other Thundercats have been enslaved by Mumm-Ra and the mutants. Most of them have been put to work in mines, but Wilykit and Wilykat are Mumm-Ra's personal slaves, and he actually refers to Wilykit as his "concubine."
Played for Laughs in Astérix and the Laurel Wreath; Asterix and Obelix need to infiltrate Roman society, so they apply to be slaves, much to the bewilderment of the slavemaster.
Not that his other slaves took their roles seriously either. The british slave refused to let him sell off the protagonists until they had haggled for a decent price. (The slavemaster was ready to give the duo away for free, since they were causing trouble and beating up other slaves.)
Gambit had the misfortune of being a child slave twice. The first time, he was stolen from the hospital as a baby by the Thieves Guild and given to a child slave trafficker and sorceror known as The Antiquary. The second time, the Thieves Guild's benefactress Candra caught him and his cousin sneaking into her home and sold him to a disgusting, monsterous creature known as The Pig, who sold children to Hydra as soldiers. It was in escaping The Pig that Gambit learned to use playing cards as weapons.
In the Italian fairy tale The Slave Mother, a peasant woman is asked by an owl whether she would rather be happy in youth or age; after she chooses age, she is carried off by pirates. Her husband and sons find, somewhat later, a treasure and move to the city; one day they buy a slave — at the husband's insistence, an old woman who can manage their household. In due course they figure out that she's the mother.
In the German folk tale The Ice Child, a woman claimed to have been impregnated by ice while thinking of her absent husband. He raised the child for some years, took him on a journey, and sold him as a slave — claiming to his wife that the boy had melted.
In Fair Brow, he buys an enslaved woman; later, he and an old man are enslaved.
In The Fledgling Year, Cor was kidnapped by slavers and spent several chapters MIA as a result until Aravis and Hana rescued him. The brutality of his experience is especially poignant not just because he’s his country’s crown prince, but also because he was raised as a slave by an abusive adoptive father, who actually tried to sell him to someone else, until he ran away. Getting dragged back into that life would be a Fate Worse than Death for him more so than for any other character in the fic.
In the second installment of Yognapped, Peva enslaves the surviving Yogscasters and forces them to work in his mines until they break bedrock, a seemingly impossible task. They accomplish it after nearly a month of work, resulting in Peva and the Ironstorm Remnants getting absolutely annihilated by the freed Herobrine. Peva survives, suffering a Villainous Breakdown after the incident.
In Don Juan DeMarco, the title character relates a yarn about being captured by slave dealers and sold into the 'service' of a lusty Sultana. Not that he seems to have minded much. It probably helped that the Sultana kept him hidden in her husband's large harem (apparently she didn't object to sharing.) This incident also occurs in Lord Byron's epic poem Don Juan, upon which the movie is partially based.
Doctor Edward Shaw of Cutthroat Island (played by Matthew Modine) was a teacher and medical doctor before being sentenced to slavery for "theft and moral turpitude" (its implied he seduced a nobleman's teenaged daughter) prior to the beginning of the movie's plot. By the end of the movie, he's free again, having become a member of a pirate band.
Sam Flynn in TRON: Legacy. When he's picked up as a "stray program", he's immediately sent to the Games Grid, where he will fight until he dies.
It's a running theme in the franchise. His father got the same treatment upon arriving in Cyberspace for the first time, and User-Believer Programs (including Tron and Ram) were conscripted into the Games as a way to get them killed. Beck was made into a game slave when he got captured. And in the Alternate Continuity of Tron 2.0, Jet is spared from execution when Mercury suggests this as his punishment instead.
In The Ice Pirates, political prisoners and others are sold into slavery after being "redesigned" lobotomized and neutered, however, females remain "fully functional." They don't "redesign" clergy (shown by a captive monk) "just in case." Unfortunately for the monk shown, a much larger prisoner beats him up, changes clothes with him and escapes.
In Tangled, the Stabbington brothers threaten Rapunzel with this.
The premise of 12 Years a Slave. Solomon Northup is a freeborn black man of New York, until he is drugged, kidnapped, and sold at auction as a Georgia runaway slave called Platt. He spends the next twelve years on three separate plantations, always seeking a path to return to his family.
Hecuba and all the princesses of Troy after The Trojan War. Except for the one who is sacrificed at Achilles' tomb — in some versions, she tells Hecuba at least she's escaping slavery. In The Iliad Hector foresees and laments such a fate for Andromache.
Well do I know that the day will surely come when mighty Ilius shall be destroyed with Priam and Priam's people, but I grieve for none of these — not even for Hecuba, nor King Priam, nor for my brothers many and brave who may fall in the dust before their foes — for none of these do I grieve as for yourself when the day shall come on which some one of the Achaeans shall rob you forever of your freedom, and bear you weeping away. It may be that you will have to ply the loom in Argos at the bidding of a mistress, or to fetch water from the springs Messeis or Hypereia, treated brutally by some cruel task-master; then will one say who sees you weeping, 'She was wife to Hector, the bravest warrior among the Trojans during the war before Ilius.' On this your tears will break forth anew for him who would have put away the day of captivity from you. May I lie dead under the barrow that is heaped over my body ere I hear your cry as they carry you into bondage.
In Beowulf, Hrothgar's queen is described as queenly and wearing gold, but her name is "Wealhtheow," which means "foreign slave." This is a possible Back Story for her, especially since the name is unique to her in Anglo-Saxon literature.
The protagonist of The Obsidian Chronicles was the sole survivor of a dragon attack on his village. The men who came to check for survivors found him... and promptly sold him as a slave to a nearby mine.
The professor in A Distant Episode by Paul Bowles is made a slave. It doesn't end well.
Several times during the course of the Gor series. Tarl's Heroic BSOD came when he chose "the ignominy of slavery" over "the freedom of honorable death."
The protagonist Dr. Cherijo Grey Veil from the Stardoc series gets enslaved by the Hsk'skt. She doesn't make a very good slave.
The main character in Trickster's Choice, by Tamora Pierce, is kidnapped and sold into slavery in a neighboring nation. This actually forms the premise of the whole duet. Luckily the people she ends up with are fairly nice as things go, although extenuating circumstances mean she is treated better than most.
She still deliberately gets herself injured during her first night in the slave pens, though, because she wants to avoid any owners who think she'd make a good bed-warmer; she deliberately makes her bruises look worse than they are, so that she'll give the impression of someone who would be more trouble than it's worth. She only finds out later that she didn't even need to do this—probably—because the Trickster god of the area is watching over her and wants her help. She's not happy to find out that she could have survived without needing to break her nose.
Shasta overhears the discussion to sell him as the newest slave of a rich Calormen military man in The Horse and His Boy and decides, with said man mount's Bree's help, to run away. It is Bree and Hwin's Back Story, as they were kidnapped from their valleys when very young and then used as Calormen mounts. And Queen Susan has reason to fear it, considering that Prince Rabadash is Yandere for her and wants her as his puppet was at any costs.
Tavia's Back Story in A Fighting Man Of Mars, though she was too young to remember. And also that of Tavan, a minor but significant character; John Carter frees him for his services and because he was obviously of noble birth gave him a place in the fleet. Plus, he turns out to be Tavia's father.
In At the Earth's Core, David Innes fights for Dian. He does not realize that after it, he could take her hand to claim her as his wife, take her hand and let go to free her, or do nothing to make her his slave. He does nothing. She is not pleased.
Male Tourists, who become either galley slaves or gladiators
The daughters of merchants who were brought along with the caravan; these appear to be the only source of harem slaves.
This is the premise of Marion Zimmer Bradley's book Warrior Woman where the amnesiac protagonist is sold as a pleasure slave to the gladiators. She becomes a gladiator herself when she halves a newbie's skull with his own sword during inspection.
A recurring plot in ''The World Of Gor'', it even occurs to Cabot more than once. Typically by the end of the book female characters learn to accept their place while male characters earn their freedom and otherwise rise above their slavery.
Edward Rutherfurd's Sarum includes a few characters who are enslaved, and treats them more realistically than many writers (e.g. a pregnant woman is terrified to be made a slave, knowing her master will probably have her baby killed at birth rather than let a useless infant become a drain on his household).
In Iron Dawn, Kepru is surprised that Barra wants to avoid the slave market, and assumes she was a victim of this trope. ("Nothing to be ashamed of: it could happen to anyone!") Subverted in that no, Barra was never a slave; she wants to avoid the market because she knows she won't be able to resist buying some out of pity.
Aminata Diallo in The Book of Negroes is made a slave early on, and stays as one for roughly half the book.
In book two in The Wheel of Time, Egwene al'Vere is made a damane by the Seanchan and treated like a dog. Although she is saved by the end of the book, it's tough on her mentally.
Several characters are also captured and made slaves for the Shaido Aiel in the later books.
In John Bunyan's Pilgrim's Progress, one character recounts his managing to evade this trope:
It came burning hot into my mind, whatever he said, and however he flattered, when he got me home to his House, he would sell me for a Slave.
Jack Chalker's Flux & Anchor series begins with the main character, Cassie, being thrown into slavery after she discovers the corruption endemic in Mother Church. She eventually overcomes this to become the most powerful woman on World and in the Church, only to be put back into slavery by New Eden when she loses both her power and her ambition to hold it.
In addition, pretty much the entire female population of New Eden can be said to be enslaved, complete with magical modifications to make it stick.
Seyonne in Carol Berg's Rai-Kirah trilogy has this as his backstory. also several other characters, since there was something of a campaign for a long time.
Mary Renault's The King Must Die is replete with Deliberate Values Dissonance here. Which is to say that since Theseus is a nice guy, when he picks his woman out of the choices, before he fights with another man, he gives orders that if he loses, they are to give her to one man and not make common sport of her, and when he survives he takes to her bed and promises that night never to give her to a guest against her will. (And the other slave women in his household don't get this, hmm?)
Mary Renault again, in The Persian Boy, the second of her Alexander the Great novels. She has her title character, Bagoas son of Artembares, describe in precise detail how he was taken by his father's enemies, sold at market and castrated. At ten years old.
In Aaron Dembski-Bowden's Warhammer 40,000Night Lords novel Soul Hunter, the navigator Eurydice is captured by the Night Lord Talos, who already has a slave named Septimus — Primus, Secondus, etc have already died. Septimus doesn't even have to ask to start calling her Octavia. On the other hand, she was always treated as a pawn while free, so when the two slaves are attacked, and Talos treats Septimus's injuries, sets out into a stronghold of his enemies to save her from Attempted Rape, and gives Septimus the best quality augmentics for his body parts injured beyond repair — better than many rich can get — it's not too surprising that she becomes a loyal slave and even accepts Octavia.
This seems to be the fate of Tsu'gan in Nick Kyme's Warhammer 40,000 novel Firedrake.
In the glutted slave markets of Aghrapur, Sultanapur, Khawarizm, Shahpur, and Khorusun, women were sold for three small silver coins—blonde Brythunians, tawny Stygians, dark-haired Zamorians, ebon Kushites, olive-skinned Shemites.
It was exactly such laughter as he had heard bubble obscenely from the fat lips of the salacious women of Shadizar, City of Wickedness, when captive girls were stripped naked on the public auction block.
In The Wonderful Wizard of Oz, Dorothy is told it is easy to find the Witch: just go into her lands and she'll enslave you. Which is what happens, though the Witch finds the Lion much harder.
Actually, the Witch ordered her servants to kill them, except for the Lion, who she thought was useful. The Winged Monkeys were only able to incapacitate the Scarecrow and the Tin Man (who Dorothy and the Witch's liberated slaves were able to find and repair later); Dorothy was spared because a blessing put upon her by the Witch of the South prevented them - or the villain - from hurting her. Taking her prisoner was the only option at that point, and the Witch simply had to bide her time until she could find a way around it.
In Ozma of Oz, the Nome King justifies turning the queen of Ev and her children to ornaments because they had been sold to him as slaves, and it was more humane than slaving in the mines.
In Ordeal in Otherwhen, Charis signs an indefinite term labor contract; she is being traded for slaves for agricultural labor.
In Judgment on Janus, Niall sells himself to buy enough drugs for his mother to have a peaceful death.
In Graham McNeill's Horus Heresy novel False Gods, Maggard is an indentured servant, but his vocal cords have been removed to keep him from speaking in the presence of his mistress, and she uses him as a Sex Slave.
In Karen Hancock's The Light of Eidon, Abramm is kidnapped and sold as a slave (first as a scribe, later to be trained as the in-universe equivalent of a gladiator) at the order of his older brother who's gone insane.
Happens to a number of characters in various books of Brian Jacques' Redwall series.
The Gladiators, by George John Whyte-Melville, has a young man from Celtic Britain captured by invading Romans and eventually becoming an emancipated gladiator.
In Stephen Hunt's The Rise of the Iron Moon, the fate of some humans under the slats.
In The Roman Mysteries, Nubia starts the series as a slave. Many other children are also kidnapped and enslaved, forming the basis of the plots for The Pirates of Pompeii and The Colossus of Rhodes. The Four Detectives are briefly captured in The Pirates of Pompeii and are going to be sold as slaves. Jonathan is also briefly enslaved in The Assassins of Rome and at the end of The Enemies of Jupiter he uses the brand mark to pose as a slave. Three of the Four Detectives are captured yet again in The Colossus of Rhodes.
In Dragonflight, the first book in the Dragonriders of Pern series, Lessa begins the story as a kitchen drudge.
In The Silmarillion, both Men and Elves are enslaved by Morgoth and his minions. A specific example would be Gwindor, who is captured and forced to work in the forges of Angband, but later escapes.
Tyrion Lannister and Jorah Mormont get caught by slavers and sold in the fifth book of A Song of Ice and Fire. Tyrion eventually talks his way out of slavery.
Kaladin spends the first book of The Stormlight Archive as a slave, having been enslaved by a treacherous aristocrat in his Back Story, he manages to win his way free at the very end of the book.
According to the 13th century Heimskringla, Olaf Tryggvason, later to be king of Norway (ruled c. 995-1000 AD), as a boy was captured by Estonian vikings in the Baltic, and spent seven years as a slave in Estonia before he was found and ransomed by his uncle.
In one episode of Star Trek: Enterprise, nine Enterprise crew are captured by Orion slavers. One (T'Pol) sells for a high figure, presumably as a sex slave. Before her new owner can even complete filling out the paperwork, the Enterprise attacks.
In Warriors' Gate, the Tharls had enslaved people in the past — "The weak enslave themselves" — and now are slaves themselves. The Doctor gives them an Ironic Echo, and one concedes the justice, but they have suffered enough.
Survivors: Tom, who gets this treatment as punishment for a murder he committed. Greg too, for trying to help him escape.
In Flash Gordon, Flash and other political prisoners are enslaved at the atomic furnace in the city of the hawkmen.
In Aida, this is how the princess, Aida, ended up in Egypt.
Religion and Mythology
Greek Mythology: Heracles/Hercules was basically forced to do whatever Hera told him to do during the Twelve Labors. One of the actual labors was cleaning out the manure from a stable, a menial task which was meant to humiliate Heracles.
However, on another occasion he was forced to atone for a murder by becoming the slave of a queen named Omphale for a time, which had a more humbling effect (in some versions Omphale forces him to wear a dress and perform tasks normally reserved for women).
...and in other versions, he's tasked with impregnating 50 women (as the amazon queen assumed this would take him a long time, leaving her plenty of time to seduce his attractive friend). He managed it in a single night and departed for his next task the next day. Some of his tasks were pretty awesome.
Plato was invited to Sicily because the tyrant Dionysius the Elder, wanted philosophers at his court. Plato showed up, gave him advice, and sufficiently offended Dionysius that he sold him into slavery, and his friends had to buy him back. This did not stop him from going to advise Dionysius the Younger a generation later, too, which ended more peacefully, if no more successfully.
After Persephone's abduction, Demeter wandered the earth, and when she finally stopped at a household, she told them she had escaped slavers who had captured her.
And in Joseph and his Brothers. He gets bought for his prettiness — as a kind of home accessory.
Also in The Bible: The Jews in general, in Egypt (early in the book of Exodus) and again when conquered by the Assyrians and Babylonians. And just after the New Testament, happens to lots of Jews when the Romans crush a couple of rebellions.note Though by then, lots of Jews were living outside of the biblical Holy Land—indeed, many never returned from Babylon—so not all were directly affected by the Roman defeat.
The women in the Greek camp in the Iliad. Also, Tecmessa, who was Ajax's captive.
This will definitely happening to anyone (Player Characters or otherwise) who are taken alive by the neogi, an evil race of bug-like creatures who first appeared in the Spelljammer setting but appear in other settings. Turning other races into slaves is their hat, so to speak, and powerful neogi even do it to weaker neogi. (They view the whole universe in terms of ownership; in their culture, the strong possess and dominate the weak.)
The dao (a type of genie of elemental Earth are another race known for being notorious slavers. Ironically, the dao themselves were forced into a type of divine slavery when their ruler was defeated by the Faceless God of the yikaria (or yak-folk), requiring the dao to serve the yikaria for "a thousand years and a year". (How much of that sentence had already passed at mainstream time is not known.) Due to this agreement, every yikaria has the ability to summon a dao - so long as he does not already have one as a servant - who must serve unquestionably until the sun has set twice.
In the 4th Edition guidebook Monster Manual 2, Slavers are one of several varieties of humans that are outlined as possible antagonists. The Lore section states, "Slavers are themselves slaves to greed and power", which is true, more often than not.
Chaos forces enslave the population when they take a planet.
The Imperium enslaves convicts.
Even Imperial Space Marines have slaves to do work that a Space Marine is not needed for. Though the Marines' slaves are generally failed Marine candidates who somehow survived washing out, and are often more than happy to help, since they're still in a better position than the vast majority of Imperial citizens. Most such slaves who appear in the fluff are immensely valued personal assistance who even receive longevity treatments that only the rich normally get.
Although Space Marine serfs are also, in some cases, even better trained than the Imperial Guard in combat, being expected to join the defence of their masters' fortress-monasteries if an enemy ever manages to get close enough to be a threat to them. In some fluff it is revealed that some Chapters have serfs who are born, raised, live their lives and die in the Chapter's service.
Wherein I spoke of most disastrous chances, Of moving accidents by flood and field, Of hair-breadth ’scapes i' th' imminent deadly breach, Of being taken by the insolent foe And sold to slavery, of my redemption thence And portance in my traveler’s history.
A standard plot in the plays of the Roman playwright Plautus. This being the best way to ensure that the adulescens can make a legitimate marriage with the "flute girl" he's fallen for: she turns out to have been captured by Pirates at a young age and is revealed to be the long-lost daughter of the next-door neighbor.
Also a massive But Thou Must, since the way you're "supposed" to do it is by willingly dressing up as a slave and turning yourself in as a failed "escapee". And needless to say, you're immediately "volunteered" for the most dangerous job available, and then again "volunteered" participate in the Gladiator Games - only by a fellow slave! Granted, you're the only one capable of doing the jobs, and this was pretty much the entire escape plan from the start, considering that winning in the Gladiator Games means you're freed from slavery and can become one of the slavers, where you then have free run of the Pitt and can do anything and everything you want to free and cure the sick slaves. If only it were that simple.
This shows up in the plots of a few characters in Valkyrie Profile, mainly in the main character's, in which she ends up getting herself killed in order to avoid being sold off by her parents.
This was part of Juhani's Back Story in Knights of the Old Republic. Turns out Revan was the one who freed her from it. You also can skewer the guy who tried to buy her on your lightsabers. You also find a small child who ran away from Mandalorian raiders who speaks mostly gibberish, a few people who were sold into slavery as punishment for debts, and you have to free Bastila from the swoop gang planning to auction her off on the galactic slave market.
In the second game, Mira was also technically a slave of the Mandalorian raiders who destroyed her home. Unlike most examples, they weren't abusive to her, teaching her how to fight and handle explosives as though she were a Mandalorian child.
In The Old Republic, the backstory of the Sith Inquisitor is that they were a former slave, who earned their freedom when they were discovered to be force-sensitive. They were then given two options; Go to the Sith Academy on Korriban for Training from Hell... or die!
Fenris from Dragon Age II got a double dose of this in his backstory. Being an elf in Tevinter, he was already born a slave. Then his master Danarius augmented Fenris with lyrium tattoos in a painful ritual that literally burned his memories away. An "honor" Fenris competed for so he could win his mother and sister's freedom. The person Fenris was ceased to exist, leaving a powerful and completely obedient Blank Slate. Fenris didn't develop a taste for freedom until a certain My God, What Have I Done? moment prompted him to flee Tevinter and never look back. He can be Made a Slave again if Hawke allows Danarius to reclaim him. Fenris will be so disheartened by the betrayal that he'll surrender without a fight. A grateful Danarius will send a letter to Hawke mentioning that Fenris' memories were wiped out again and he is once more an obedient slave, and he extends an invitation to Hawke to visit his estate in Tevinter.
In the Hegemony Series, if you manage to capture retreating enemies, you get to do this to them. It's a cheap alternative to hiring workers for the mines or supply duties.
Generic Bandits in the Fire Emblem Series try to do this to pretty much any female character. They have nothing to do with the plot, they serve no purpose except to teach the player the ins and outs of the system, and it happens so frequently that it's become a Running Gag among the fanbase.
Vattu is sold into slavery by her tribe as payment to the Sahtan empire.
Terinu: Teri's best friend Matt is a notable case. He was indentured to a psychotic Space Pirate when he was eight to pay for his father's drinking induced debts. It says something about how sucktacular his family's life was that this was an improvement.
In Dragon Mango, some captured goblins are forced to work until they pay off their debt.
Joe in Statless And Tactless talks the group into enslave Mari because it actually protect her more then harm her. Also it would piss off her player, Ian.
Though this is technically supposed to just be for appearances and not actual slavery, Soo immediately takes a liking to the idea of owning someone.
Futurama, "A Pharaoh To Remember": Fry, Leela and Bender are made slaves to an Ancient Egypt-themed planet. The Pharaoh is about to free them when he dies, and Bender scams his way into being the next Pharaoh, leaving Fry and Leela as slaves until the end of the episode.
Also happens when Hermes and LaBarbara are enslaved on vacation. Hermes uses his powers of Bureaucracy to "efficiently" dump all the work on one Australian guy and free everyone else.
A tamer example appears in an episode of My Little Pony: Friendship Is Magic. Diamond Dogs (a pack of dogs who love jewels) see Rarity using her magic to find gems, so they capture her and force her to work for them. It's never directly called slavery, but still. She manages to get them to let her go (and go off with all the gems) through the power of whining.
In Beast Wars, this is how Rampage winds up serving Megatron. Rampage's spark is immortal, so Megatron cuts off a piece of it and places it in a box that he can use to inflict excruciating pain on Rampage if he disobeys.
Unfortunately still happens everywhere, yes even in first world countries. As many as 27,000,000 of them.
A convoluted example comes from the early history of the United States. The first slaves in Britain's American colonies were prisoners transported to the New World and sold to the plantation owners as craftsmen, house servants, and field workers. While these "indentured servants" never regained their freedom, upon reaching adulthood any children born to them became free after a period of six years spent working for their parents owners as "repayment" for the food, shelter, and education they were provided as children.
Modern example: This is a huge problem in the cocoa industry. Children are bought cheap (or kidnapped) in Ivory Coast and forced to work. It is estimated that 95% of the kids are not paid for the work, and due to the heavy loads they carry and machetes they use they often get injuries that go untreated. Around 42% or so of cocoa comes from this place.
When the Greek philosopher Phaedo of Elis was young, he was taken prisoner in war and was subsequently sold into slavery in Athens, where he was forced into prostitution. Eventually he met Socrates, who took a liking to him and had him freed.
La Malinche, a Nahua woman who lived in what is now Mexico, was given to the Spanish conquistadors as a "servant". She ended up serving Hernan Cortes as a translator and eventually became his mistress, and bore him a child.
Los Zetas, a major Mexican crime syndicate, has been known to kidnap telecoms engineers to build and maintain their communications network. Unlike their usual kidnapping victims, ransoms are not offered and the victims are believed to be killed when they have outlived their usefulness.