As the bastard son of Lord Roose Bolton, Ramsay originally used the traditional surname for bastards born in the North, and was known as "Ramsay Snow". However, he has recently been legitimized as Lord Roose's lawful son, and has therefore been officially renamed "Ramsay Bolton".
Ramsay is violent and sadistic, and fond of the ancient Bolton practice of flaying. During the War of the Five Kings, he is dispatched by his father to retake Winterfell from Theon Greyjoy. Ramsay massacres the ironborn garrison, puts the castle to the torch, and takes Theon prisoner. He subjects Theon to extensive physical and psychological torture, turning him into a broken pet named "Reek".
Ramsay Snow, better known as "The Bastard of Bolton", is Lord Roose Bolton's bastard son and only living child following the death of Domeric Bolton, as well as the only possible heir to House Bolton. He stayed behind at the Dreadfort to rule as its castellan when his father left for the south to fight in the War of the Five Kings.
Ramsay keeps a pack of dogs, which he employs for hunting.
After Winterfell is seized by Theon Greyjoy for the ironborn, Ramsay is dispatched by his father Roose Bolton to re-take it in the name of King Robb Stark. Ramsay's forces besiege the castle, and he infuriates Theon by blowing a horn all through the night. The following morning, Theon rallies his men to defend the castle, but he is betrayed and knocked out cold by his men, who accept Robb Stark's offer of mercy for the ironborn garrison if they surrender and hand over Theon. However, the castle is sacked by Ramsay afterwards and instead of letting the ironborn walk free, he flays them alive.
Following the Sack of Winterfell, Ramsay and his men take Theon to the Dreadfort, where the ironborn prince is subjected to gruesome tortures. Embarking on a twisted campaign of psychological manipulation, Ramsay poses as an ironborn emissary of Theon's sister, Yara, and falsely claims to have been sent by her to liberate him.
Ramsay Snow sends a false report to Harrenhal, where the main force of the Northern army has established, of the sacking of Winterfell by the ironborn, of the disappearance of Bran and Rickon Stark, and the unknown whereabouts of Theon Greyjoy.
Later that evening Ramsay returns, and releases Theon, provides him with a horse and tells him to ride east to Deepwood Motte, where his sister is waiting for him. Theon's captors, however, track him down and capture him again. As punishment, their leader attempts to rape Theon. Ramsay appears and swiftly dispatches the kidnappers with bow and arrow, deepening the bond of trust between them.
Afterward Ramsay promises Theon to take him to Deepwood Motte. Some time later the men reach a holdfast; Theon questions them, having to sneak inside since Yara's men are loyal to her. Ramsay warns Theon that some of the men belong to his father Balon. As the mysterious boy struggles to open a locked gate Theon confesses his jealousy of Robb's status, the murder of the two boys he passed off as Bran and Rickon, and acknowledges that Eddard Stark was his true father. After opening the gate Theon and Ramsay enter a darkened room. The young man lights a torch and Theon, much to his horror, notices he's back in the torture chamber. Armed men enter and Ramsay claims that Theon killed their comrades and escaped but he has brought their captive back. Kicking and screaming, Theon is refastened to the rack, as Ramsay drops his facade, grins sadistically and tells the men to put Theon "back where he belongs".
Ramsay awakens Theon with a horn to continue torturing him. He threatens to remove Theon's pinky finger if he cannot guess Ramsay's true identity and their current location. After several guesses, Ramsay tells Theon he is correct in guessing that Ramsay is the brother of Torrhen Karstark, and that they are in Karhold. However he then points out that Theon never asked if he was a liar. He admits that he was lying, and begins flaying Theon's finger.
Theon is freed from his constraints by two young women, Myranda and Violet. They give him water and clean his wounds. Theon is apprehensive about their aid, until they disrobe and begin pleasuring him. The three are soon interrupted by Ramsay, who enters the chamber wielding a knife. After taunting Theon about his sexual prowess, he orders his men to restrain Theon and then removes Theon's genitals.
Ramsay admits that the rumors about Theon were true, and that he did have a "good-sized cock", before momentarily tricking Theon into believing that the pork sausage he is eating is his penis. Ramsay talks about amputees having phantom limbs and wonders if Theon will have a phantom penis, feeling an itch whenever he sees naked girls. When Theon begs to be killed, Ramsay states that he is no good to him dead. Ramsay decides to give Theon a new name, and beats him until he starts calling himself "Reek". Ramsay also sends a letter to Balon Greyjoy with a box containing Theon's penis. He threatens to flay every ironborn in the North alive if they have not left by the full moon.
Some time later, Ramsay hunts a girl named Tansy in the woods with his hounds, Myranda, and Theon, recently renamed "Reek". With bows in hand, he and Myranda gleefully pursue Tansy, firing arrows at her as they go. Ramsay explains that Tansy had made Myranda jealous so she has to go because she causes too many problems otherwise. Myranda manages to strike Tansy with an arrow in the leg before Ramsay happily releases his dogs on her, killing her. Shortly afterward, Lord Roose Bolton arrives at the Dreadfort where Ramsay waits for him. Roose introduces Ramsay to his newly acquired wife, Walda Bolton, and asks to see his captive. Ramsay also greets Locke and congratulates him for his mutilation of Jaime Lannister. Locke assures him that the Kingslayer had screamed loudly enough that Ramsay would have enjoyed it.
Ramsay brings "Reek" to his father, who is furious with Ramsay for torturing and mutilating a valuable hostage. Roose explains that he wanted to use Theon as a bargaining chip to rid the North of Iron Islanders, and for that he needed him unharmed. Roose chastises Ramsay for his actions, and laments placing too much trust in him. Ramsay tries to prove that his torture had a purpose. He orders Reek to shave him with a razor, demonstrating that he will never betray them, and adds that his method revealed key information; that Theon did not kill Bran and Rickon Stark. Theon also tells them that their half-brother Jon Snow may be sheltering them at the Wall.
Finding it enlightening, Roose sends Locke after the Stark boys and tells Ramsay to take Moat Cailin, a vital base in the North, from the Greyjoy forces, and that if he can take it in the name of their family, he will reconsider Ramsay's position.
Ramsay engages in particularly violent sex with Myranda, forcing her to strangle him as they both climax. Meanwhile Yara Greyjoy, intent on rescuing her brother Theon from Ramsay's clutches, leads a force of fifty ironborn reavers in rowing boats up the Weeping Water towards the Dreadfort. They manage to enter the castle and find Theon in a kennel alongside the dogs, but he refuses to go, having become loyal to Ramsay. Ramsay soon arrives and drives the ironborn from the Dreadfort with his soldiers. When an ironborn asks if they are leaving without her brother, Yara declares her brother to be dead.
Ramsay besieges Moat Cailin and sends Reek to treat with the ironborn garrison, posing as Theon Greyjoy. Theon vouches for Ramsay's promise of safe passage back to the Iron Islands if they surrender. The ironborn surrender, and Ramsay instead flays them all alive. Having taken Moat Cailin, Ramsay and his father meet on an open field. Roose hands him a document legitimizing his bastard son and granting him the right to call himself "Bolton". Ramsay is delighted, and they then make their way towards Winterfell
While eating with his father, Ramsay tells him that he managed to "persuade" House Cerwyn, one of House Stark's vassals, to pay their taxes by flaying Lord Medger Cerwyn, his wife and older brother alive, and coercing their son to pay in their stead. Finally out of patience with his son, Roose scolds Ramsay for his actions, because since Tywin Lannister is dead, the Lannisters will no longer support them and they will not be able to hold the North with terror alone, since the Northern Houses will eventually rise up against them at the slightest excuse. Roose then reveals that he has arranged for Ramsay to marry Sansa Stark to placate the Northerners. When Sansa arrives, Ramsay greets her with politeness. Later, Petyr Baelish speaks with Ramsay, who promises never to harm Sansa after Baelish subtly warns him against it. As Ramsay takes his leave, he expresses his gratitude to Baelish for finding him a suitable match.
Later, Myranda tells Ramsay of her jealousy for Sansa, since Ramsay had previously promised to marry her while he was still a bastard. Ramsay coldly denies his attraction to Sansa and openly states his opinion of her beauty, and becomes angry when Myranda threatens to marry someone else and leave him. Ramsay approaches Myranda and reminds her of what he does to people who bore him. He forces himself on Myranda, who bites his lip but reciprocates. Ramsay later confronts Reek about his encounter with Sansa, and warns him not to keep secrets from him again. Though he seems like he will punish Reek, he ultimately forgives him. At dinner, Ramsay initially expresses delight at his wedding to Sansa, but things turn sour when he brings Reek into the room and coerces him into apologizing to Sansa for allegedly killing Bran and Rickon, and suggests that Reek should give Sansa away at their wedding. Roose puts a stop to his son's behavior by announcing that Walda is pregnant with a boy. Ramsay's expression turns angry, as he sees Roose and Walda's child as a potential threat to his position as his father's heir. Later on, Ramsay asks his father about his mother. Roose tells him about how he killed a miller and raped his wife because they got married without his consent, and sometime later, the miller's wife came to the Dreadfort and left the infant Ramsay with him. Roose had been prepared to throw Ramsay into the sea to drown, but stayed himself because he knew, deep down, that Ramsay was his son. Roose then states that Stannis Baratheon is at Castle Black and will likely attempt to take Winterfell from them during his journey to King's Landing, and Ramsay promises to help his father counter Stannis.
Later, when Theon comes to fetch Sansa for the wedding, she refuses to hold Theon’s arm, even after he pleads her to, saying that Ramsay will punish him if she doesn’t. Reek then gives Sansa away to Ramsay, and they wed in front of the Godswood. After retreating to the bedroom, Ramsay asks Sansa to take her clothes off. Reek is about to leave but Ramsay tells him he must stay. Ramsay quips to Reek:, "You grew up with her as a girl, now watch her become a woman." Annoyed by Sansa's hesitance, he pushes her face-down over the side of the bed and angrily rips open the back of her dress. As he unbuckles his clothes, Sansa obediently remains still but begins crying softly. Reek is visibly distraught and begins silently crying himself, as Ramsay proceeds to roughly consummate their marriage.
Over the next few days, Ramsay continues to rape and beat Sansa every night. He is informed by a reluctant Reek of Sansa's plan to escape by signalling Brienne of Tarth and Podrick Payne to come and rescue her, and retaliates by flaying Sansa's elderly maid who delivered Brienne's message to her. Ramsay forces Sansa to look at the corpse, and walks with her across Winterfell, boasting about how he will succeed his father as Warden of the North and she will be his Wardeness, but Sansa counters that Roose is expecting a boy with Walda, a boy who may be Ramsay's baby brother but may still become Roose's true heir, since Ramsay is still technically a bastard, who was even legitimized by Tommen Baratheon, who Sansa claims is also a bastard. Ramsay, visibly angered, counters that even bastards can rise, like her half-brother Jon Snow did when he became the new Lord Commander of the Night's Watch, and taunts Sansa for not knowing it. He then orders Sansa taken back to her chambers and locked up again.
As Stannis approaches Winterfell, Ramsay is present at a council meeting on how to counter him. While Roose suggests that they wait out the siege inside Winterfell and allow Stannis and his army to die in the cold, or even for Stannis's men to mutiny against him, Ramsay advocates taking twenty of his best men to face Stannis in the open, on the basis that Stannis will not leave the North so easily, and they need to show the rest of the North how they will deal with Southern invaders.
Ramsay takes his men into Stannis's camp and they torch some of his tents, severely depleting Stannis's men and resources, and manage to flee back to Winterfell without being spotted.
However, this does not stop Stannis. Though his numbers are greatly reduced, he leads a siege to Winterfell. Ramsay, however, leads the Bolton forces into battle and massacres Stannis's men, sustaining minor cuts to the face in the process. In the aftermath, Ramsay slays a half-dead man, despite his claims of surrender, and heads back to Winterfell, saying that "my wife will be lonely", though he is unaware that Sansa has escaped from the castle with Theon.
Having discovered Myranda's body and Sansa and Theon's escape, Ramsay mourns Myranda in his chamber, remembering that even when they met as children, Myranda was the only one who showed him no fear, something Ramsay admired. Ramsay promises to avenge Myranda, and has Maester Wolkan feed her body to the hounds. Later, while speaking with his father, Ramsay is congratulated for his victory over Stannis but chastised for allowing Sansa and Theon to escape. Ramsay claims he has sent men and hounds to find them, but Roose counters that if Sansa does manage to escape from the North, he will disinherit Ramsay in favor of his unborn son with Walda, leaving Ramsay visibly shaken.
Harald Karstark later arrives at Winterfell to notify Ramsay and Roose that Theon and Sansa have disappeared. Ramsay, assuming they will go to Castle Black to seek shelter from Jon Snow, suggests that they march on the Wall, kill Jon and retrieve them, a suggestion Roose immediately dismisses on the basis that Jon is a bastard, though Ramsay counters that so was he before Roose had him legitimized. Still, Roose argues against Ramsay's plan on the grounds that killing the Lord Commander of the Night's Watch would only further alienate the rest of the Northern houses, many of which are still angry with the Boltons for their part in the Red Wedding. Maester Wolkan announces that Walda has given birth to a baby boy. Ramsay is barely able to restrain his anger. Roose calms him by promising him that he will always be his firstborn, but Ramsay chooses not to take any chances and stabs his father in the chest, killing him instantly. Ramsay orders Wolkan to announce that Roose was poisoned by their enemies, and to bring Walda and the baby to him. After glimpsing his new half-brother in the Winterfell courtyard, Ramsay leads Walda to the kennels and locks them inside, setting the hounds to maul his stepmother and brother to death, proclaiming himself the new Lord Bolton, Lord of Winterfell and Warden of the North.
Later, Ramsay is approached by Lord Smalljon Umber, who asks for House Bolton's support in fighting Jon Snow and the Wildlings, as Last Hearth is the northernmost castle in the North. Despite frequent insults against his late father, Ramsay agrees on the condition that Umber pledge fealty and kneel before him. The Smalljon refuses both times, instead bringing Ramsay a gift in the form of a captured Osha and Rickon Stark. Upon seeing Shaggydog's head as proof of Rickon's identity, Ramsay sarcastically welcomes the youngest Stark home.
Ramsay sends a letter to Jon Snow at Castle Black, where he rightly assumes Sansa has headed. He demands that Jon returns Sansa to Winterfell, and threatens to kill every wildling who survived the Massacre at Hardhome, let his men rape Sansa, and maim and kill Jon and Rickon should he refuse. Tormund, unofficial wildling strongman, claims his 2,000 fighters are not enough to face the 5,000 soldiers of House Bolton. Jon and Sansa decide to try to unite the houses of the North against the Boltons, as Jon is the son of a legitimate Warden of the North. Together with Tormund, they start planning to expell House Bolton from Winterfell and restore House Stark's hold in the North.
Ramsay and Smalljon Umber meet with Jon, Sansa, Tormund, Davos and Lyanna at the battlefield the day before the battle. Jon offers Ramsay a chance to settle their dispute in one on one combat but Ramsay refuses, citing almost certain victory due to his significantly larger army. Ramsay offers surrender terms saying he will pardon Jon for breaking his Night's Watch vows if he will hand Sansa over, which is ignored. Sansa asks for proof of Rickon's capture, and he responds by throwing the decapitated head of his direwolf, Shaggydog, at her feet. Sansa refuses the terms of surrender and tells Ramsay he will die the next day, before riding off.
The next day, as the battle begins, Ramsay arrives holding the captive Rickon. He sets him free, but then shoots him dead with an arrow as he is inches away from Jon's reach. With Jon now defenseless in the middle of the battlefield, Bolton archers fire volleys of arrows in his direction with the Bolton cavalry charging at him as well. The Stark cavalry begin their charge to meet the Bolton cavalry, narrowly saving Jon from being trampled to death and forcing them to abandon their initial battle plan. Ramsay executes a pincer movement with his cavalry, completely encircling the Stark/Wildling army. As the Bolton army advances, Petyr Baelish and Sansa arrive with reinforcements courtesy of House Arryn, and their cavalry quickly flanks the encircling Bolton army, which is decimated.
Defeated, Ramsay retreats with his remaining allies, and closes the gates, confident in their ability to withstand siege, and readies his archers. However, with the help of the giant Wun Weg Wun Dar Wun, Winterfell's gates are breached, and the remaining Bolton forces defeated, although Wun Wun is incapacitated by injuries sustained by archers, and Ramsay delivers the killing shot. Having nowhere else to go, he finally accepts Jon's offer to a one-on-one duel while wielding a bow and arrow. He shoots at Jon several times, but Jon blocks them all with his shield and catches Ramsay by surprise by knocking him to the ground and savagely beating him to near death. Ramsay is spared, however, when Jon decides not to kill him outright.
Ultimately, Ramsay is chained up in a dungeon cell. At nightfall, Sansa goes to the cell. He goads her by telling her how she will never be rid of him because he is "part of her now". In response, Sansa tells him that he will be forgotten, and his House will cease to exist. She releases his hounds, which had not been fed for seven days, into his cell. Despite his confidence that they would never harm him, Ramsay finally loses his composure and desperately attempts to order them to stop as they sniff at him hungrily. He is ultimately mauled and devoured by his own hounds.
A bastard son of Roose Bolton, the since-legitimized Ramsay captured Theon Greyjoy and tortured him until Theon was a shell of his former self and renamed "Reek". Ramsay married Sansa Stark and forced Theon to bear witness to their wedding night. After his stepmother, Walda, bore his father a trueborn son, Ramsay murdered the baby, Walda and Roose, securing his place as Lord of Winterfell. He lost the castle in the Battle of the Bastards and was killed by Sansa Stark.
Ramsay is sadistic, savage, wild, psychotic, and completely capable of committing unspeakable atrocities without remorse, simply for pure amusement. Ramsay fully admits - and indeed revels in the fact - that he tortures and kills innocent people for no reason whatsoever, and that they do not deserve what he is doing to them. It simply makes him feel powerful.
Ramsay is fearless - almost a beast in human skin - glorifying in the violence of personal combat. Ramsay does not rave and rage, however: he has a pervasive, playful, childlike giddiness as he inflicts pain on others, from flaying men alive to hunting and killing girls for sport. The cold-blooded torture of other people is little more than a hilarious game to Ramsay.
In his own twisted way Ramsay is actually quite intelligent, possessing a certain "low cunning" with which he tricks his enemies. He particularly enjoys playing mind games with his enemies using psychological torture, often tricking them into trusting him only to then break his promise - such as when he was torturing Theon, promising he would release him if he guessed where they were, then afterwards simply said "you forgot to ask if I'm a liar" and then flayed his finger anyway. One of Ramsay's favorite "tricks" is to kill enemies after they have surrendered to him, while under a flag of truce.
On the other hand, Ramsay is very impulsive, not fully considering the long term consequences of his actions. His father chides him that the entire point in taking Theon hostage was to keep him unharmed, so they could trade him back to the Greyjoys in return for their withdrawal from the North, and torturing him only harmed his future political plans. Continuing along this path, after the Boltons are in control of the North, when Lord Medger Cerwyn refuses to pay Ramsay taxes or even acknowledge Bolton rule, Ramsay flays Cerwyn alive along with his wife and brother while forcing his son to watch, and puts the corpses on public display. Roose again has to angrily warn his son that this disproportionate brutality is severely damaging their long-term position - but Ramsay largely ignores his warnings, instead privately holding a massive feast for himself even as other lords are worried about stockpiling provisions for the winter.
Ramsay is shown to be greatly frustrated by his bastard status, and is easily angered when he is referred to in such a way. When he is legitimized as "Ramsay Bolton", he is clearly overwhelmed to the point that he almost cries with joy and gets on his knees to solemnly promise his father that he will live up to his family name and traditions and not fail him. Despite his legitimization, however, he is still wary of his status as Roose Bolton's bastard-born son, and knows deep down that if his father is to have a legitimate son with his new wife, it may very well be a threat to his future claim. A possible source of this resentment is his jealousy of fellow bastard Jon Snow, who was raised by his father, Ned Stark, along with his trueborn sons and eventually rose to become Lord Commander of the Night's Watch, and his desire to rise high in the world like Jon did (although it is unknown if Ramsay met Jon personally or merely heard about him). He is also visibly stunned when he learns that he is actually the product of a violent rape and that his father nearly killed both him and his mother when he was a baby, implying that despite his negative qualities, he held his mother in high regard when she was alive, and even remarked to Theon that she tried to encourage him to be kind as a child (though he didn't listen).