Theon is the heir of Lord Balon Greyjoy of the Iron Islands. He has been a hostage of House Stark since his father's failed uprising against King Robert Baratheon. Despite his status, Theon became a close friend to Robb Stark. However, after Robb sent him as an emissary to his father during his war against the Iron Throne, the Greyjoy prince turned on the Starks and joined Lord Balon in his campaign to seize the North. He took over Winterfell and installed himself as Prince of Winterfell until he was betrayed by his own crew and delivered to House Bolton shortly after. As a prisoner of Ramsay Snow, the "Bastard of Bolton", he has been subjected to physical and psychological torture and mockingly renamed as "Reek".
Theon is the youngest son of Lord Balon and Lady Alannys Greyjoy. Balon is the head of House Greyjoy and Lord of the Iron Islands. The Iron Islands are one of the constituent regions of the Seven Kingdoms and House Greyjoy is one of the Great Houses of the realm. House Greyjoy rule the region from their seat at Pyke and Balon also holds the title Lord Reaper of Pyke.
Theon was born at Pyke. He is Balon and Alannys' fourth child after Rodrik, Maron, and Yara. Eight years before the start of the series Balon rose in rebellion against the Iron Throne. The ironborn were crushed in a war led by King Robert Baratheon and Lord Eddard Stark. Theon's brothers were both killed in the fighting. Balon surrendered and was allowed to remain Lord of the Iron Islands on the condition that Theon remain a hostage and ward of Eddard Stark. Theon's sister Yara remained on the Iron Islands. Despite his status as a hostage at Winterfell, Theon was been treated well by the Starks, and he and Robb Stark became best friends. Theon is a skilled archer. His cocky arrogance and cavalier actions contrast with the staid ways of the North.
Theon is present during the execution of Will, a deserter from the Night's Watch. He holds the scabbard of Ice, the greatsword of House Stark, as Lord Eddard Stark draws it to behead the condemned man. On the way back to Winterfell, the party finds a disemboweled stag dead in the road. Looking for the killer, they find a dead female direwolf and five pups huddled by the corpse for warmth. A broken piece of the dead stag's antler is embedded in the direwolf's neck. Theon suggests killing the pups, but Jon Snow convinces his father that this is an omen as there are five pups and five Stark children, Eddard consents to allowing his children to adopt the pups. Just as the party leaves, Jon finds a sixth pup, an albino. Theon ruefully points out that this one belongs to Jon. Later, Robb, Jon, and Theon get shaves and haircuts, as they ponder the impending arrival of the royal party, notably the reputation of Queen Cersei Lannister as a great beauty and the poor reputation of Prince Joffrey Baratheon.
After the royal party's departure, an assassin attempts to kill Bran, who had fallen during one of his climbs and remained comatose. Theon learns that Catelyn has found evidence implicating the Lannisters in Bran's 'accident' and the failed assassination. Theon and Robb suggest taking revenge through military action, but Maester Luwin counsels patience. Catelyn and Ser Rodrik Cassel depart for King's Landing, leaving Robb in command of the castle. Theon is present when Robb frostily receives Tyrion Lannister on his way back from the Wall. Afterwards, as Tyrion is leaving to stay in a brothel, Theon condescendingly tells him to ask for Ros. Tyrion insults Theon about the defeat of the Greyjoy Rebellion led by Theon's father, Balon Greyjoy, and how Theon is now Eddard Stark's "lackey". Whilst boasting about his family's exploits and heritage, he is put down by Maester Luwin. He reacts angrily to a further insult from his favorite prostitute, Ros, after sneaking her into the castle to engage her services.
Theon and Robb exchange views over the matter of Jory Cassel's death and the growing Stark-Lannister animosity in King's Landing. Robb brusquely reminds Theon that he is not a Stark. Bran is taken prisoner by wildlings in the forest near Winterfell and Theon saves him by shooting Stiv, the wildling leader, in the back with an arrow. Robb is angry at him, as Bran could have been hurt. Theon counters that he just saved Bran's life, and Robb was too hesitant to kill. Taking pride in his action, Theon says that you're only considered a real man in the Iron Islands once you've killed your first enemy. With the departure of Ros for King's Landing, Theon is left at the castle and is bored. He accosts the surviving wildling prisoner, the spearwife Osha, as she is now a servant at Winterfell. Theon pushes his weight around, insisting that she call him "my lord", even though his father still holds the title. He is warned off by Maester Luwin who reminds Theon that he of all people should know that being a guest and a prisoner are not necessarily mutually exclusive.
Robb summons his banners to war when word comes of Lord Eddard's arrest. Theon tells Robb that it is good that he is afraid, as it shows he is not stupid. As the northern army marches south, Theon advises Robb at strategy meetings and greets Catelyn when the army meets her on the road. When a Lannister scout is captured, Theon obscures their maps and battle plans, to Greatjon Umber's amusement. Reaching the Twins, Theon shoots down several ravens leaving the castle bearing messages from Lord Walder Frey, allowing Catelyn to negotiate an alliance. Theon fights alongside Robb at the Battle of the Whispering Wood, where Jaime Lannister is taken prisoner. When Robb laments the loss of 2,000 of his men in the feint at the Battle of the Green Fork, Theon assures him that songs will be sung of their bravery. Robb responds that they will not hear them. After news arrives of Eddard's execution, Robb Stark is proclaimed the King in the North by his lords bannermen. Theon asks first if they are brothers, now and always. When Robb's answer is yes, Theon swears his sword and fealty to Robb's service, proclaiming Robb as his King.
Theon appeals to Robb to seek an alliance with his father, Balon Greyjoy, reasoning that Robb needs a fleet to attack King's Landing. Despite Catelyn's reservations that Balon Greyjoy cannot be trusted, Robb sends Theon home to Pyke as his envoy. Theon seduces the daughter of the ship's captain and tells her about how he will be welcomed home. He is deflated at the lack of a reception for his return. His sister Yara poses as a stranger and offers to give him a ride to the castle. She wants to see what Theon has grown up to be. He flirts with her relentlessly and brags about his own importance. Balon greets Theon coolly, believing that he has forgotten his roots and become loyal to the Starks in his time away. He insults Theon's fine clothes given to him by the Starks, and is furious when Theon tells him that Robb thinks of him as a brother. Yara reveals her deception and Balon compares Theon to his sister unfavorably. Balon rejects the alliance Theon suggests and is insulted that Theon thought he would accept being given a crown. He reminds Theon that they pay the iron price and take what they want.
Balon reveals that he plans to attack the North while it is poorly defended. Balon gives Yara a fleet of thirty ships to take Deepwood Motte and insults Theon by assigning him a single vessel to raid fishing villages on the Stony Shore. Theon considers informing Robb of the plot but decides that his loyalty lies with his family. Having decided to betray House Stark he is baptised in the name of the Drowned God as Balon and Yara watch. He takes command of the Sea Bitch but finds his crew unruly. His first mate Dagmer Cleftjaw tells him that he must prove himself to the men and that ironborn do not follow orders. Theon senses the opportunity to attack Torrhen's Square to lure the Stark garrison away from Winterfell. His plan is successful.
Theon has his men seize the poorly defended Winterfell. He forces Bran Stark to yield to him by threatening his people. His men capture Ser Rodrik Cassel coming back from Torrhen's Square, and Rodrik is openly defiant, calling Theon a traitor. Ser Rodrik regrets that he gave him weapon training and even spits in Theon's face. Dagmer insists that Rodrik must be killed to maintain the respect of the men. Rodrik baits Theon into performing the execution himself. Theon botches the beheading, taking three swings and a kick to accomplish it.
Theon is seduced by Osha, who then frees Bran and Rickon. When Theon wakes the next day, he is told that Bran and Rickon have escaped. He is angry at his men for allowing children and the simpleminded Hodor to escape. Lorren implies that Theon is actually to blame for their escape by allowing himself to be seduced by Osha. Theon, in turn, responds to this insolence by publicly striking Lorren repeatedly. Despite his attempts, Theon is unable to find the escapees. Unwilling to appear weak, he has Dagmer murder two boys from a farm and burn their bodies. He displays the corpses at Winterfell and claims they were Bran and Rickon. Theon sends word to Yara to bring him 500 men as reinforcements. She arrives with just twenty men and warns him that everyone in the North wants him dead because of his killing the Stark boys, and he is too far from the sea to supply or reinforce his position. Yara tells him about how she remembers him as a child, demanding but sweet. She urges him to abandon Winterfell, return to the Iron Islands, and not to die so far from his home, but he refuses to give up his prize.
Winterfell is surrounded by Northmen under the command of Ramsay Snow. Besieged with no hope for relief, Theon laments to Maester Luwin the horrible things he has done in search of respect and power. Theon admits that he always felt like an outsider among the Starks and wanted to win the affection and approval of his true family. Luwin says that he knows that Theon is not the ruthless man he has been pretending to be. He suggests that Theon flee to the Wall and join the Night's Watch to save his life and attempt to redeem himself. Theon refuses to deviate from the course he has set, saying that is too late, as he has gone too far down this course for him to ever pretend to be anyone else. He readies his men for a glorious death in battle, giving a rousing speech, but is betrayed and knocked out by Dagmer, who plans to turn him over to the northern forces so the rest of them can go home. Luwin attempts to aid Theon but is stabbed in the abdomen by Dagmer, who then has Theon dragged away with his head covered by a cloth bag.
Roose Bolton's bastard son Ramsay Snow has been sent to secure Winterfell from the ironborn and bring Theon back to Robb Stark alive. Roose is double-crossing Robb and after the ironborn turn on Theon and surrender themselves to Snow's forces, he kills them all and secretly captures Theon
Theon is kept prisoner in the Dreadfort, although Theon is unaware where he is. He's repeatedly tortured by a group of men, some of whom are dressed in the garb of Greyjoy men. One of the men gleefully pries off Theon's fingernails with a knife while the others drive a screw through his foot. After enduring hours of torture Theon is given some reprieve. Ramsay Snow pretends to Theon that he is a servant and approaches him and claims Ramsay has been sent by Yara to rescue him. Before dawn Ramsay returns and cuts Theon free and provides him with water and a mount. Ramsay advises Theon to keep heading east where Yara is waiting for him. Theon says he'll make the boy a lord of the Iron Islands for his actions. The boy replies by saying "We're not in the Iron Islands".
As Theon rides east, an arrow narrowly misses his head, and Theon sees that his captors are following him. After a harrowing chase the former Prince of Winterfell is knocked from his horse by a blow from a flail. The men hold Theon in place as the leading torturer prepares to rape him. Theon's pleas for them to stop fall on deaf ears but then the leader is pierced by an arrow. Ramsay has returned and swiftly kills all his men. Ramsay helps Theon to his feet and tells him to come with him, because he is far from home and winter is coming.
After rescuing him the boy promises Theon to take him to Deepwood Motte to see Yara. When Theon questions his savior, Ramsay lies that he is ironborn as well, growing up on Saltcliffe, and he witnessed Theon being shipped off to Winterfell. Some time later the men reach a holdfast, and Theon questions why they have to sneak inside when surely Yara's men are loyal to her. Ramsay warns Theon that some of the men belong to his father Balon who wants him dead. As the Ramsay struggles to open a locked gate Theon confesses his sins. He wanted so desperately to impress his father but he knows now that Eddard Stark was his true father. After opening the gate Theon and Ramsay enter a darkened room. The youth lights a torch and much to Theon's horror he's back in the same torture chamber in the Dreadfort. Armed men enter and Ramsay claims that Theon killed their comrades and escaped but he has brought their captive back. Kicking and screaming a heartbroken Theon is refastened to the rack.
Theon is awakened by the ringing of a trumpet. Ramsay 'begs pardon' for rousing his guest. Theon tries to mumble something but fails. Ramsay understands his prisoner requires water but pours it out all over the dungeon floor to further torment him. Ramsay proposes to play a game to pass the time and he asks the heir to Pyke which body part he does not need. Hearing this Theon vows to tell his captor all he wishes to know. The cruel boy merely mocks him stating that Theon already told him everything of value. Ramsay goes on saying that he realizes Theon wants to know who he is and why he is being tortured. The young man makes a proposal: If Theon guesses correctly who he actually is Theon is the victor, but if Theon begs his tormenter to remove his finger he wins. Theon then asks if winning said game will secure his release. Ramsay the mocks Theon's naîveté stating there is no happy ending in store for him. Theon does guess correctly that he is still in the North. However when the former prince of Winterfell supposes that Ramsay is a son of Rickard Karstark he is revealed to be wrong. Ramsay slowly flays his captive's pinkie stating that Theon first should have asked if he was a liar. Theon begs for the finger to be cut off which delights Ramsay since Ramsay has won the 'game'.
Theon is released from the cross by two beautiful young women. The women put Theon to bed and they then proceed to fondle him sensually. Both wenches have heard that the heir to Pyke is well endowed and are hoping to get first hand experience. Theon is distrustful at first fearing that this is another of his tormenter's tricks. When both wenches disrobe and straddle him, Theon's resolve to resist weakens. Suddenly the familiar horn sounds and Ramsay enters. He too has heard how large his prisoner's penis is and surmises it is Theon's favorite body part. When the sadistic Ramsay brandishes an odd knife Theon realizes Ramsay means to emasculate him. Horrified Theon begs for mercy, but Ramsay quips that this is mercy as he is not killing, but merely altering Theon.
Theon wakes in his strung up position while the boy eats a long plump sausage nearby. Ramsay mocks him as he laughs about his severed penis and wonders if Theon will have phantom feelings for his lost body part if he goes near any pretty women. Theon asks Ramsay to kill him, but Ramsay tells him he is much more valuable to him alive. He renames him Reek (because he smells bad) and demands that Theon say that his name is Reek. Theon refuses at first then after being beaten about the face meekly and utterly broken says his name is Reek.
Ramsay has sent Theon's severed penis to his family in Pyke with a letter detailing his Sack of Winterfell and his demand that the ironborn withdraw from the North or Ramsay will send them more of Theon's body parts. Balon refuses to surrender, saying that Theon was a fool for disobeying his orders and attacking Winterfell and that, as his castration means that he is no longer capable of producing heirs, he has no value whatsoever. However, Yara defies her father and prepares the fastest ship in the fleet and the strongest men on the Iron Islands to sail on the Dreadfort and rescue Theon.
Reek accompanies Ramsay and Myranda on their hunt for Tansy, however he struggles to keep up with them due to his injuries. When Myranda brings down Tansy with an arrow to the leg Ramsay asks Reek if it was a good shot. Reek calls it a fine shot while addressing Ramsay as "Master" and Myranda as "My Lady". Reek watches in silent horror when Ramsay orders his pack of hounds to maul Tansy to pieces.
Ramsay brings Reek before Ramsay's father, Roose Bolton. Roose is angered that Ramsay has damaged a valuable hostage, whom he intended to trade for the ironborn-occupied Moat Cailin. To demonstrate their captive's submissiveness, Ramsay orders Reek to shave him. Reek reveals to Roose that he did not murder Bran and Rickon Stark, and that they may be with Jon Snow at the Wall. Ramsay then reveals to Reek that Robb Stark is dead, and was stabbed through the heart by Roose. Reek holds the razor at Ramsay's neck briefly, but continues shaving.
Outside of Moat Cailin, Ramsay goes over Reek's mission with him one last time: he is to enter Moat Cailin under the guise of Theon Greyjoy, prince of the Iron Islands, and attempt to negotiate with the ironborn garrison holding it in an attempt to convince them to surrender the fortress to the Boltons. Reek rides up to the fortress gate, and almost blows his cover when asked to identify himself, yet manages to regain his composure and convince the ironborn to let him to enter. Upon riding into Moat Cailin, Reek finds it in a state of death and decay, littered with corpses and the few remaining men ravaged by disease and exhaustion. He introduces himself as Prince Theon and truthfully informs the ironborn that he has been a prisoner of House Bolton and has been sent to Moat Cailin as their envoy. He reads the terms that House Bolton has laid out for the ironborn, promising them safe passage home if they peacefully surrender Moat Cailin. However, Ralf Kenning, the garrison commander of the ironborn, decries Reek's words as those of a "whipped dog" and that he is no true ironborn, nearly causing Reek to become unnerved and drop his facade. However, Reek is saved when one of Kenning's men suddenly buries an axe in his head and accepts Reek's terms of surrender. However, the ironborn are promptly massacred and flayed by Ramsay and his men upon surrendering Moat Cailin.
In the aftermath, Ramsay meets with his father and presents him with the Greyjoy banner that was flying over the fortress. In recognition of this, Roose presents Ramsay with a decree of legitimization, making him officially a member of House Bolton. Delighted at the knowledge he will succeed his father as Warden of the North, Ramsay and Reek accompany Roose's army as it approaches the ruins of Winterfell, with Ramsay gleefully informing Reek that he's ready for a hot bath.
Reek walks through the partially-repaired Winterfell and is clearly shaken when he sees freshly flayed corpses being hung on the castle walls, which reminds him of the alleged burned corpses of Bran and Rickon. Later, while Ramsay and Roose Bolton discuss their delicate position as the new Wardens of the North, Reek serves them their food. When his childhood friend, Sansa Stark, arrives in Winterfell, Reek watches her arrival from a distance. Later, as Sansa explores the courtyard, Reek avoids her, but appears to be struggling not to call out to her.
Later, while sleeping in the kennels, Reek is accosted by Sansa, who had been led there by Myranda. Reek shakes his head at her and tells her she shouldn't be there. Ramsay later confronts Reek about how Sansa approached him and chastises him for keeping it a secret from him. Though he seems like he will punish Reek, he ultimately forgives him.
As the Boltons eat, Ramsay coerces Reek into apologizing to Sansa for allegedly murdering Bran and Rickon, while Ramsay suggests that Reek walk Sansa down the altar at their coming wedding, to Reek's discomfort.
On the night of the wedding, Reek, once again assuming his previous identity as Theon Greyjoy, arrives to escort Sansa to Ramsay, though Sansa, still angry with him, refuses to allow Theon to hold her arm, even when Theon claims Ramsay will punish him. Theon walks Sansa through the Godswood to the Heart tree, and gives the bride away. After the wedding, Theon leads Sansa and Ramsay to their new chambers, but Ramsay orders Theon to remain with them to watch what is to come. Having personally been on the receiving end of Ramsay's brutality, Theon tries to look away, but Ramsay repeats the order, and Theon is forced to watch, which he does. Theon is visibly horrified as he watches Ramsay rape his childhood friend, making her cry, and silently cries himself.
A few days later, Reek brings Sansa her breakfast, closing the window when he notices her shivering in bed. When Sansa realizes Reek is there, she tries to talk to him and get him to help her. Reek continues to deny that he is Theon, until Sansa accuses him of betraying her family, and reminds him that he is Theon Greyjoy, son and heir of Balon Greyjoy, Lord of the Iron Islands, and that he can redeem himself by lighting a candle in the broken tower in order to signal Brienne of Tarth and Podrick Payne to come and rescue her. Though Reek takes the candle, he reluctantly informs Ramsay of Sansa's plan in order to spare her further pain should it fail, but it is implied during his conversation with Sansa that his original personality of Theon Greyjoy is slowly beginning to resurface.
When Reek next brings Sansa breakfast, she confronts him about why he revealed her plan to Ramsay, and he responds that it was to protect her, since he has found out there is no escape from Ramsay: as Theon Greyjoy, he tried numerous times, but Ramsay always found him and took away pieces of him until there was nothing left of Theon anymore, only Reek. Sansa coldly expresses approval, adding that if she could do what Ramsay did to him all over again, she would. Reek shamefully owes to her that he deserved it as he did terrible things, specifically killing "those boys". Enraged by his reference seemingly to her brothers as "those boys" rather than Bran and Rickon, Sansa vehemently demands to know why they should be dead while he still breathes the air, forcing Reek to finally admit that they were not in fact Bran and Rickon, only two farm boys. In light of this admission, Sansa's anger towards Reek cools but when she presses him as to where they might have gone, calling him Theon again, he breaks down and runs out the room, crying, "Not Theon! Reek!".
When Sansa finally succeeds in breaking out of her room and lighting the candle in the tower, she is confronted by Reek and Myranda on the catwalks, with Myranda pointing a bow at her. Reek begs Sansa not to resist, but Sansa welcomes her fate. However, when Myranda claims that she will spare Sansa and merely maim her, Reek remembers the role Myranda played in his castration. Unwilling to let Sansa suffer the same fate, Reek grabs Myranda and pushes her off the catwalk to her death. Now Theon Greyjoy once again, he takes Sansa and they run when the Boltons arrive after defeating Stannis Baratheon. With no other choice, and aware of what will come when Ramsay finds Myranda's body, Theon and Sansa jump from the balcony to the snow below. Whether or not they survive the fall remains uncertain.
Sansa and Theon land uninjured and manage to escape into the nearby woods. Pursued by Ramsay's men and hounds, Theon and Sansa cross the river and take shelter but their scent is picked up by the hounds. Theon urges Sansa to flee Jon Snow at Castle Black while he holds them off, but they see through his ruse and find Sansa. Brienne of Tarth and Podrick Payne appear to fight the Bolton soldiers, and Theon kills the last one, saving Podrick's life. He witnesses Brienne pledge her service to Sansa, which this time she accepts.
As Brienne talks with Sansa, Theon overhears that she crossed paths with Arya, while gathering wood to help Podrick start a fire, though he is wary of it, since it may alert Ramsay or his men. Sansa and Brienne decide to head to Castle Black to get to Jon, who will protect them from Ramsay, and though Sansa promises to tell Jon the truth about Bran and Rickon to stop him from hurting Theon, Theon doubts that Jon will forgive him for betraying Robb, executing Rodrik Cassel, and slaughtering Jack and Billy. Theon claims he does not want to be forgiven, even by joining the Night's Watch, and instead decides to return home, knowing that Sansa will be safer with Brienne and Podrick. Before his departure though, Sansa embraces Theon in gratitude for helping her escape Ramsay.
Theon arrives at the Iron Islands and receives a harsh reception from Yara, who is still angry about the time he refused to be rescued from the Dreadfort, saying that good men were lost that night. Weeping, he apologizes several times, but she doesn't want to hear it. She accuses him of trying to take advantage of their father's murder to become King of Pyke. Incredibly upset, he says he had no idea Balon was dead until he arrived. She demands to know what he wants, and he says she deserves to be ruler of Pyke and he will support her claim to the Salt Throne
During the Kingsmoot, Theon openly declares his support for Yara's claim to the Salt Throne; stating that she is a warrior, a reaver, and most importantly an Ironborn. While many declare their support for Yara, her claim is challenged by their uncle Euron Greyjoy, who publicly humiliates Theon for his past defeats and emasculation. Yara then accuses Euron of murdering their father. To their surprise, Euron admits murdering Balon but claims that he did it because he was leading them to defeat. Theon then points out that Euron was gallivanting on the high seas while Yara was leading Ironborn ships and men in battle. When Yara proposes building a massive fleet to conquer the mainland, Euron counters by offering to seal an alliance with Daenerys Targaryen in order to defeat the mainland lords. The crowd then elects Euron to be their next king. While Euron is being baptized by Aeron, Theon, his sister, and their supporters flee on the best ships in the Iron Fleet.
As part of Daenerys's plan to lay siege to King's Landing, Theon and Yara are tasked with escorting Ellaria Sand and her daughters back to Dorne. On the voyage back to Sunspear, Theon finds himself uncomfortable when Yara gets intimate with Ellaria, especially when Theon rebuffs Ellaria's advances (as she is not aware of what Ramsay did to him) and Ellaria demands that he refill her jug (though Yara tells Ellaria not to treat him like a servant). Moments later, Euron's fleet attacks without warning. Despite fighting bravely and cutting down many of Euron's men, Theon watches helplessly as Euron takes Yara hostage, daring him to intervene. Not wanting his sister to die, Theon jumps overboard. Upon surfacing, Theon can only watch as Euron's flagship sails away, having decimated their entire armada, and sees the corpses of Obara and Nymeria Sand impaled and hanging from the ship's bowspirit.
Theon is later rescued from the Narrow Sea by one of the few surviving ships loyal to Yara. When their captain, Harrag, questions him about Yara's fate, Theon claims that he tried to save her. Harrag chides Theon, saying that he would be dead if that were true.
Theon later returns to Dragonstone and is shocked to be met on the beach by none other than Jon Snow; the two have not seen each other since Jon left Winterfell for the Wall, over six years ago. Theon hesitantly greets him and asks if Sansa is all right; Jon angrily grabs him by the collar, saying that Theon saving Sansa from the Boltons is the only reason he won't kill him then and there for betraying House Stark in the first place. Theon informs Jon and Davos that Yara was taken captive by Euron and he needs Daenerys's help to get her back, only for Jon to tell him that she has left Dragonstone to carry out her own attack on the Lannister armies.
Theon accompanies Jon's group to the meeting with Queen Cersei where Euron attempts to force him to swear fealty in order to save Yara, though Theon says nothing. Theon meets with Jon before he prepares to leave back with Daenerys to the North as they reflect on their enmities as Theon was conflicted between his family and the Starks though Jon remarks that Ned was more of a father to him than Balon ever was. Jon remarks that he is both a Stark and a Greyjoy, encouraging him to rescue his sister from Euron. Theon attempts to round up Yara's army though Harrag refuses to help due to viewing Theon as a coward for abandoning her. The two get into a fight with Harrag gaining the upper hand and almost beating Theon to death, who refuses to back down. Unaware of Theon's castration at the hands of Ramsay, Harrag fails to injure Theon by kneeing him in the groin and is beat into submission by Theon who rallies the remaining forces.
Formerly a ward of House Stark and prince of the Iron Islands, Theon was quick to support his friend Robb’s rebellion against King Joffrey. But upon returning to his ancestral home on Pyke as Robb’s envoy, Theon joined his father’s forces and betrayed the family that raised him. Theon seized Winterfell but was taken prisoner by Ramsay Bolton, who tortured him into renouncing his identity. He lived in terror of Ramsay but mustered up the courage to help Sansa Stark escape the castle. Upon returning to Pyke and hearing about his father’s death, he supported his sister’s claim to the Salt Throne. When Euron Greyjoy won over the Ironborn instead, Yara and Theon fled to Meereen where they arranged an alliance with Daenerys Targaryen. Theon accompanied his sister on a mission to collect the Dornish fleet, but jumped overboard to safety when his uncle attacked them at sea, leaving Yara behind. Ashamed of his actions, Theon has rallied the remaining Ironborn to rescue his sister.
Before his capture by Ramsay Snow, Theon is shown to be rather arrogant, narcissistic and vain, but fundamentally not malicious. He expected acclaim in a multitude of situations even if he were the only one expecting acclaim for it - when he shot a wildling to save Bran, his perspective believed that he had simply saved Bran's life and not risked hitting Bran with the arrow, and also when he returned to the Iron Islands he expected to be coated in glory for being allegedly the only living heir of Balon Greyjoy. He was both baffled and offended that he did not receive a hero's welcome back to Pyke. Also, in order to appear like a strong, accomplished young man, he would gloat over things in an almost ridiculous way - he gloated to Osha that he was the man who captured her, even though Robb Stark fought and captured her. Beneath his confident exterior, however, he is insecure, weak, and unsure of himself. This stems particularly from the fact that he was raised by the Stark family since he was nine years old as their ward/hostage after his father's failed rebellion against Robert Baratheon, and while he grew up with the Stark children and at at their table, he was always reminded in some way that he was not truly part of the family.
This subject is shown to irritate Theon greatly, demonstrated when Ros and Tyrion Lannister mention it. His insecurity also leads him to question which is his true family: the Starks or the Greyjoys. Though his father Balon and sister Yara are initially successful at using it to sway Theon to their side when Balon decides to fight the Starks instead of aid them against the Lannisters, this still causes a great deal of conflict in Theon. The ironborn take pride in attacking and stealing from others, "paying the iron price" as they call it, but Ned Stark set the example for Theon that other people should be dealt with according to a basic code of honor and justice. Theon tries to become a ruthless ironborn raider to appease his biological father and find a true home again, but the conscience that he developed living with the Starks makes it difficult for him to live up to these expectations. In his efforts to show great strength, Theon proves himself to be something of a hypocrite: when he seizes Winterfell, he promises to Bran that no one would be harmed if Bran surrendered, but minutes later he completely shattered his promise by beheading Ser Rodrik Cassel, consequently ripping apart his suggestion that he would be a merciful lord and ignoring the wise advice of Maester Luwin. Since he was the self-proclaimed Prince of Winterfell, he was completely in his right to decide to spare Ser Rodrik, but he chose the wrong option and humiliated himself even further in the process.
It is only after Theon becomes a prisoner of the Boltons and realizes that his father has no intention of rescuing him that he admits, to himself and to Ramsay Snow, that Ned Stark was his "real father", and laments Ned's execution in King's Landing. Even throughout Theon's capture of Winterfell, he is shown to be in a constant battle with himself, implying that he knows deep down that invading his childhood home for his father was far from right. Maester Luwin even points out to Theon that all of this is just an act to live up to his father's expectations, and that Theon himself must know that his betrayal at Winterfell is wrong. Theon resignedly admits to Luwin that he is correct, but that he can't stop because he has already come too far to be forgiven, and refuses to join the Night's Watch, where all of his crimes would be forgiven, out of shame (and partially out of fear that Jon Snow might kill him in retribution for allegedly murdering Bran and Rickon).
After being tortured by Ramsay Snow in the dungeons of the Dreadfort for over a year, Theon's original personality has been seemingly obliterated, and he is little more than a broken and half-insane prisoner. Among various tortures, Ramsay cut off several of his fingers and toes, flayed off sections of his skin, and even cut off his genitals. Ramsay even mockingly renamed him "Reek", physically and psychologically torturing him to accept it as his name, and deny that he ever was "Theon Greyjoy". Ramsay also psychologically tortured him with fake escape attempts or promises of rescue, before recapturing him, so now Reek thinks any possibility of escape or fighting back against Ramsay is simply another ruse. He lives in great fear of Ramsay, desperate to avoid angering him, and is in such a state of traumatic shock that he is very withdrawn and submissive.
However, despite his previous actions, Reek appears to have retained a strong love and loyalty to the remaining Starks, demonstrated on several occasions: he is visibly shocked when Ramsay gloats about Robb's death, briefly holding a razor to Ramsay's neck and appearing on the verge of slitting his throat (though he doesn't because Roose and Locke are present); he appears hesitant about telling them that Bran and Rickon may be sheltering at Castle Black with Jon Snow, knowing that it may lead to their deaths, but does so anyway to avoid angering Ramsay; he silently cries and briefly looks angry when Ramsay rapes Sansa, and does his best (or what he thinks is the best) to keep Sansa from angering Ramsay and suffering more at his hands, and even goes as far as to confess to Sansa that he deserved what he suffered under Ramsay and that he deserved to be Reek for what he did to the Stark family. However, when pushed too far, Theon ultimately abandons his Reek persona and chooses his loyalty to the Starks over Ramsay, by killing Myranda and helping Sansa escape from Winterfell, though still believing himself unworthy of anyone's forgiveness for betraying the Starks, who were the only ones who ever treated him like family.
Despite this admission, Theon still expresses shock after learning of his father's death when he returns to the Iron Islands. Though his sister Yara is still angry with him for refusing to be rescued, they reconcile when Theon offers to support Yara's claim to the Salt Throne. While initially despondent, Theon regains some of his bravado during the Kingsmoot to select the next ruler of the Iron Islands. Giving a brief rousing speech, he manages to convince many of the gathered Ironborn to join him in supporting his sister's claim to the Salt Throne, his speaking skills demonstrating that "Reek" has all but been obliterated for good and Theon Greyjoy restored, though he and Yara are outmanuevered by Euron, who wins many over by offering to seal an alliance with Daenerys Targaryen.
After escaping Euron with his sister Yara, Theon slides back into his despondent state and is troubled by his role in the death of the orphan boys; believing that he should hang for his crimes. Yara counsels him to rediscover himself so that they can secure an alliance with Daenerys and retake the Iron Islands from their uncle Euron. While negotiating with Daenerys, Theon does not display reluctance for the Ironborn to cease raping, pillaging and reaving, and nods at Yara to tell her to agree with Daenerys, demonstrating that despite his recovery, he is still greatly traumatized by his torture by Ramsay, and apparently wishes to lead a more peaceful life in order to prevent it from happening again, though it is currently unknown whether or not Theon knows of Ramsay's death, or how he will react when he hears of it.