|“||My son didn't brand you for being loyal to Ivar! He branded you for being disloyal to Ragnar, and everything Ragnar stood for! And if I have to die for what Ragnar and I believed in, it is worth it.||”|
Lagertha was brought up by her father to be a shield-maiden. At an unspecified time, Ragnar went to Lagertha's home to confess his love for her, but he was set upon by a bear and an enormous hound who guarded her home. Ragnar killed the bear with his spear and strangled the hound with his bare hands, thus gaining her hand in marriage. It is unknown if Ragnar's story is real or a child-friendly tale to his son Björn referencing his battle with Rollo, who was known as a "bear," over Lagertha's love, as Lagertha also had a relationship with Rollo and is unsure who Björn's biological father is.
Lagertha lives on a small farm in a village outside Kattegat with her husband Ragnar, her twelve-year-old son Björn, and eleven-year-old daughter Gyda.
Lagertha is hunting eels and fish with Gyda in the river near their farm. Gyda tells her mother that she has started bleeding. Lagertha replies that this means she is now a woman no longer a child but asks to cradle her once she passes away. Lagertha is happy and relieved when Ragnar returns home from fighting and raiding in the Eastern Balts. The family celebrates that night.
Ragnar wants to take Björn to Kattegat to swear allegiance to the reigning chieftain, Earl Haraldson, and complete the ceremony acknowledging him as a man by earning his arm-ring. Lagertha does not think Björn is ready and tries to change Ragnar's mind, but he refuses.
While her husband and son are away, Lagertha is teaching Gyda how to weave on their loom when two drunk men invade their home. Lagertha sends Gyda out to the goats to protect her. Once Gyda is gone, Lagertha tells the men that she will offer them food and drink but nothing more. When they threaten to rape her, she informs them that they "couldn't kill her in one hundred years." She successfully fights them off.
Upon Ragnar and Björn's return home, Ragnar asks Lagertha is anything happened during their absence. She doesn't mention the bandits she killed, but instead says she "needs to ride him." They immediately go off to have sex, leaving Björn waiting outside. That night, Ragnar tells Lagertha of his plan to explore the west with a few good men and a sturdy ship. When she learns that she cannot go too, Lagertha is offended and protests, but Ragnar insists that she stay since she is the only one he trusts to watch their farm and children. Resistant, Lagertha fights with her husband, only to be stopped by their son.
When Ragnar returns from his voyage, he brings a ship full of treasures and a few Christian monks, including a young man named Athelstan, who can speak their language. The Earl, pleased with the bounty, decides that everything is his, though Ragnar and his men can each have one item. Obviously angered by the Earl's decision, Ragnar chooses to keep Athelstan and takes him home as their slave. Lagertha is confused as to what Athelstan talks of when he talks about his god before the two have rough sexual intercourse making lots of noises and groans, causing Athelstan not to sleep. Lagertha can be seen thrusting into Ragnar before the two then go to Athelstan and ask him to join them, which he declined as he has taken a vow of celibacy. Despite Athelstan's status as a captive, however, he is generally well taken care of.
The next trip to England has been sanctioned by Earl Haraldson. Now that they have Athelstan to watch over their farm and children, Lagertha is brought on the journey by Ragnar. Upon their arrival, they are met by a group of King Aelle's soldiers inviting them to meet their king. Distrust on either side eventually leads to a battle, with all but one soldier killed. The Vikings continued on to a nearby town and promptly raided it, though, with information learned from Athelstan, they wait until Sunday to attack the church.
During the raid, Lagertha stopped Knut, Haraldson's half-brother sent to spy on Ragnar, from raping a Saxon woman. With redirected anger, Knut attempted to rape Lagertha and is subsequently killed with his own knife. She managed to quietly leave the scene, only to be met by Ragnar and the other men who have since finished with the church. He asked Lagertha about Knut and told the group of what had happened. Ragnar expressed his concern by saying that he hoped to kill him. While Lagertha said there were no witnesses, she knows her crime is still punishable by death.
At the beach, the Vikings are met with another group of soldiers whom they easily defeat. Upon their return to Kattegat, again laden with goods, they are greeted with cheers and praises, though Earl Haraldson is quick to realize that his half-brother is missing. Ragnar took the blame for Knut's death, saying he killed Knut because he tried to rape Lagertha. Haraldson had Ragnar imprisoned and planned to try and execute him, almost convincing Ragnar's brother, Rollo, to betray him. During the trial, however, it is Haraldson who is ultimately betrayed by Rollo as he testified in support of his brother, thus freeing Ragnar of his charges. Rollo later revealed to Lagertha that he did it not for Ragnar but for her. Although Lagertha has long been pursued secretly by Rollo, she constantly rejects him, and Ragnar remains oblivious to his brother's affections.
Earl Haraldson, now hellbent on destroying Ragnar, tried many times to kill him and all those who approve of him. He and his men raid their farm and quickly destroy everything, the lives of people who tried to fight back or run. Lagertha, however, managed to escape and hide with her children and Athelstan. An injured Ragnar later joined them and together, the group found refuge at Floki's home.
Ragnar soon decided to challenge Haraldson in a duel to the death, worrying Lagertha. The night before, in the midst of love-making, Lagertha asked her husband not to fight as he is still badly injured. Ragnar, however, emerged victorious in the battle against Haraldson and became the new earl. In the midst of a party following a lavish burial for the former earl, Lagertha announced that she is pregnant. A pleased Ragnar insisted that the unborn child is a boy, just as the gods have predetermined, as the Seer once foretold.
Months into her pregnancy, Lagertha is once again left alone at Kattegat as Ragnar sailed for England. At this point, Lagertha has become responsible for overseeing varying disputes among the townspeople to maintain order. Lagertha's leadership was tested when a man brought his wife with an infant. The man claimed that a young man stayed at their house for three days, and nine months later, his wife gave birth to a child when the couple had went years without conceiving. Upon learning that the visitor's name was Rig, Lagertha demonstrated her knowledge and told them that Rig is another name for their Norse god Heimdall. She then told the man that he should consider himself blessed that the god chose them, and warns him that if any harm comes to the child or his wife, he will have to answer to her.
Later, Earl Haraldson's widow, Siggy, requested to become Lagertha's servant. Initially hesitant, Lagertha agreed. Unfortunately, Lagertha had a miscarriage and upon Ragnar's return, Ragnar is devastated. Promised many sons by the gods, Ragnar began to doubt that it is Lagertha who will provide them for him as they fail to conceive another child, no matter their efforts. Frustrated with their inability to produce the sons Ragnar was promised, both Lagertha and Ragnar ask the gods for help during the traditional pilgrimage to Uppsala, where they honor the gods with sacrifices.
During this time, Ragnar met King Horik and pledged his service to him, in return for more manpower for his future travels to England. Following the sacrifice, King Horik immediately sent Ragnar and a few other men to Götaland for negotiations, leaving Lagertha alone and worried that her husband will seek out another woman to have sons with. The negotiations eventually fall though, though Ragnar's men spy on a beautiful young woman bathing. The woman, named Aslaug, demands an apology from Ragnar, and, by using her wits to solve his riddle, soon intrigues Ragnar. The pair eventually have sex, infuriating his son with Lagertha, Björn, who is upset that his father is cheating on his mother. Regardless, Aslaug soon becomes pregnant. While Ragnar is gone, Lagertha and the remaining people of Kattegat have been fighting a losing battle with a plague. Lagertha is left to grieve one of the the many victims, her and Ragnar's own daughter, Gyda.
In Kattegat, Björn reveals Ragnar's infidelity to his mother. Though initially, the couple seem to overcome the adultery, this changes when the heavily pregnant Aslaug comes to Kattegat. Ragnar asked if he may marry both of them, for the sake of their children. Lagertha is disgusted and too insulted to tolerate such disrespect, chooses to leave him, joined by Björn.
In the time that passes, Ragnar becomes the father to several sons by Aslaug, fulfilling the prophecy. Lagertha has since remarried, settling in Hedeby with the wealthy Earl Sigvard. Unfortunately, she seems less than pleased with him, though he claims to have wanted her for a long time. Lagertha is trying, and failing, to elude Sigvard. He says his wife she should be by his side when he entertains guests. Lagertha says she will not be insulted as he does not love her or her son. Sigvard slaps her and tells her that he does love them both, then apologizes for hitting her.
Later that night, Björn confronts his mother about her husband’s violence. She tells him it won’t happen again, but Björn is unconvinced. He later tells his mother that, while Ragnar and his men have been away, their former home of Kattegat has been taken over by Jarl Borg. Lagertha tells her son that she will convince her husband to help. Later that night, Sigvard stumbles into the bedroom, apparently after having a few drinks. Lagertha appraches the subject of Ragnar, but Sigvard won't hear of it and attempts instead to make love to her. She refuses his advance which causes Sigvard to become rough and attempt to rape her. Outside the door, Björn can hear the commotion and draws his knife; Lagertha manages to throw Sigvard off and tells him to never to treat her like that again. She opens the door to find Björn and thanks him, but says he will not harm her. Sigvard passes out.
A few days later, Lagertha, Björn, and a small army join Ragnar. It has been four years since Ragnar has seen Lagertha and his son, now a young adult, which gives Ragnar great happiness to see how much his son has grown. Inside, Lagertha greets her former brother-in-law and Siggy, then heads over to Aslaug and her sons. Though the air is stiff, Aslaug thanks Lagertha for her help and Lagertha dotes on the children.
When she returns to Hedeby, she finds her husband as violent as ever. The final straw for Lagertha, however, comes after Sigvard has her brutally beaten, after which he begins to disrobe her in front of their dinner guests. Lagertha grabs a knife and stabs him in the eye. While Sigvard screams in pain, Einar steps up and silences him by lopping off his head. After a few tense moments, the Hall erupts in applause and Lagertha is made the new earl.
Now free from her husband, Lagertha, the new earl, asks the Seer if she will have any more children, to which he replies no, but relays what the gods have shown him. Lagertha is unhappy with the prophecy and how cryptic it is. She asks instead when she will die. The Seer does not know that either, only that her death has already been decided by the gods.
Before leaving once more for Wessex, Lagertha speaks to her trusted second-in-command Kalf about another marriage proposal she has received. Kalf says the man has much to offer her. She asks why he does not ask for her hand. Kalf explains that he has nothing to offer her and so the marriage would not benefit either of them. Lagertha smiles.
Lagertha takes several men and women to Wessex, with intention of creating a thriving settlement, though not all her subjects agree with this plan. Once there, King Ecbert shows a keen interest in her and tries to get in her favor. She notices his stares, but does not rebuff his attentions. Ecbert picks up a handful of soil and offers it to Lagertha. They agree that fertile land is a better gift than jewels. King Ecbert invites Lagertha and Athelstan to his villa, where he bestows another gift, this time, a beautiful necklace. Lagertha is flattered and allows him to put the necklace around her neck. They stay for a few days before returning to the settlement.
A few days later, King Ecbert, who simply can not seem to stay away, visits Lagertha again, who now greets him in English. The King is impressed and, once again, has a gift for her: a plow, designed to dig deeper into the ground and turn the soil as well. He says she and Athelstan are always welcome in his castle, whenever they may choose. The offer of hospitality is taken up and Lagertha returns to Ecbert's castle. He shows her the Roman baths and invites her, Athelstan, and Judith for a dip. Soon, Lagertha and Ecbert are wrapped around each other kissing, causing Judith to abruptly leaves the bath and Athelstan follows. Lagertha and King Ecbert take little notice, however, and continue having sex. Later, Lagertha flirts briefly with Princess Kwenthrith.
Upon returning home, she finds that Kalf has taken over her earldom. She asks Ragnar to help her recover it, and, although he joins her in speaking with Kalf on the matter, he only goes to ask for his help is attacking Frankia. Ragnar then leaves Kalf to deal with his ex-wife on her own. Though Lagertha develops an intense hatred for Kalf, their past follows them and Kalf silently watches over Lagertha during the Siege of Paris. Lagertha will have nothing to do with the man, and refuses to listen to him when he warns her that something doesn't feel right. Unable to convince her with words, Kalf takes it upon himself to knock her out and take her away, only seconds before a wave of arrows fly towards them. Lagertha awakens later to find her son Bjorn has been wounded during the battle. Like any mother would do, she rushes over to him and scolds Ragnar for not watching over him. Ragnar disagrees, of course, as Bjorn is a man after all. With the Vikings still recovering, Ragnar orders another attack. Led by Lagertha, Rollo, and Kalf, they manage to pass the bridge, but they are once again pushed back. Siegfried is captured and executed.
As Lagertha recovers from the disastrous siege attempt, Kalf makes his intentions clear: he desires her with all his heart. Lagertha says that should she accept his offer, then he should know that one day she will kill him for usurping her earldom. Kalf accepts and the two make love.
Ragnar secretly meets the Franks, and although offered gold and silver, Ragnar doesn't accept. Instead, he asks to be baptized and be buried in the city. The Vikings place Ragnar into a wooden coffin and escort it to the gates of Paris, where they meet the Bishop. The coffin is brought inside the Cathedral to be blessed, but Ragnar suddenly jumps out of the coffin alive. He takes Princess Gisla as a hostage and forces the guards to open the gates. Bjorn is standing in front of the city with the Vikings behind him and they enter the city. When Ragnar exits Paris, Björn catches and holds him. Bjorn later defends himself and tells Largertha, Rollo, and Floki he only did what his father asked of him. The Vikings leave Rollo to stay in Frankia with a small party while the rest of the Vikings sail back to Kattegat.
Lagertha returns to Hedeby after invading Paris with Kalf, Torvi, and Erlendur. Earl Kalf announces that he and Lagertha will share the Earldom, to the dislike of Einar. Kalf invites Einar and his men to vote to exile Lagertha, then turns on them, killing the dissidents and allowing Lagertha to kill Einar. Lagertha sleeps with Kalf and he tells her he loves her. Lagertha reveals to Kalf she is pregnant, and Kalf asks her to marry him. Just before their wedding, Lagertha stabs and kills Kalf, and reclaims her status as Earl. When Ragnar announces his plan to raid Paris, Lagertha and Harald join him as they set sail. A storm throws the Viking ships off course. Lagertha, Ragnar, and Harald arrive in Frankia where they set up camp. Once the remaining ships arrive, the Vikings sail up river towards Paris. As the ships approach Paris, they see Rollo waiting with his new French allies. Ragnar suggests attacking from both the river and by land. Lagertha and her warriors attack from the marshes but warriors become stuck in the marsh. Rollo fires upon them and the ships. As the ships approach the forts, Rollo orders the Franks to raise a metal chain between them, which capsizes some ships. Lagertha retreats, and the Franks begin to set the Viking ships on fire.
The Vikings retreat, and Ragnar's leadership is questioned by Harald, but Lagertha continues to support Ragnar. Ragnar tells Bjorn to land near a cliff, and reveals a new plan. They will take the ships overland, behind the Frankish forts. As the Vikings carry their ships overland, Harald and Halfdan kill a Frankish family. Lagertha has a miscarriage and is comforted by Ragnar. Rollo leads his remaining ships into battle. Halfdan, Floki, and Lagertha are wounded in the battle. Ragnar and Rollo begin to fight. The Franks gain the upper hand, and Ragnar tells Bjorn to take Lagertha and retreat. The defeated Vikings return home.
Ten years pass. Ragnar has disappeared. Thorhall delivers the news to Aslaug and Bjorn that the Norse settlement in England had been slaughtered, and that Ragnar has a son named Magnus in Wessex. Ragnar eventually, returns and asks Lagertha to accompany him to England but she refuses. Ragnar apologizes to Lagertha for everything he did. Lagertha and Aslaug perform a sacrifice to the gods for their sons. Lagertha tells Aslaug she can never forgive her for taking Ragnar, and that she will never be Queen of Kattegat. Lagertha imprisons Ubbe and Sigurd, and attacks Kattegat, intending to replace Aslaug on the throne. Lagertha attacks Kattegat, but Aslaug renounces herself as Queen, promising Lagertha that her sons will not seek revenge. In exchange, she wants safe passage to leave. She also says that Ragnar and Ivar died in a storm Lagertha initially agrees, but then kills Aslaug. Ubbe and Sigurd arrive to find Lagertha in the Great Hall. Ubbe challenges Lagertha's warriors in an attempt to kill her, but fails. Astrid tells Ubbe and Sigurd that they will die if they harm Lagertha. Lagertha considers the consequences of Ragnar's death, while his sons start to plan their revenge. Lagertha orders defences to be built around Kattegat. Ivar challenges Lagertha to single combat, but is refused, and promises that he will kill Lagertha one day. Lagertha asks if a son of Ragnar will kill her and the Seer says yes. Ivar and Ubbe attempt to kill Lagertha but are stopped by Bjorn, who makes clear that his brothers will have to kill him before Lagertha. Earl Jorgensen volunteers to be sacrificed to assure victory in the coming war. She kills him as an offering to the gods. Lagetha discovers that Kattegat is being infiltrated. Kattegat is attacked by Egil and his men, but they are repulsed and Egil is captured. Torvi is severely injured. Under torture, Egil confesses to Lagertha that he had been paid by King Harald to attack her, Egil says to Lagertha that King Harald ordered him to attack Kattegat, shocking her as he was a sworn ally.
King Harald heads back to Kattegat only to find Lagertha waiting for him, Lagertha suggests that Harald was expecting to find Egil in her place, so he could take over the kingdom. Harald confesses and dares that she kill him. Harald is held prisoner by Lagertha. He proposes an alliance with her through marriage, but she refuses and rapes him. Harald's men free him and capture Astrid as they leave Kattegat. Ubbe arrives at Kattegat. There Ubbe agrees to ally with Lagertha against both Ivar and Harald. Floki returns to Kattegat with tales of a fabulous new land and recruits settlers to return, but Lagertha forbids him from taking her warriors away. Lagertha finds out from Guthrum that Floki has secretly recruited settlers to leave with him. Lagertha meets with Floki and lets them leave because she sees no point in keeping these warriors here against their will.
Lagertha warns Margrethe that if she continues to plot against her she will cut out her tongue and enslave her. Hakon, a fisherman who was bribed by Astrid, informs Lagertha that at the next full moon Ivar and Harald will attack Kattegat together. Lagertha has allied with King Svase, welcomes her son Bjorn, and introduces him to the king and his daughter Snæfrid. Lagertha witnesses Bjorn breaking up with Torvi and then he ass Lagertha to marry Snæfrid. Lagertha and Svase agree to the marriage. Lagertha and her allies discuss how to respond to Ivar's attack, and decide to meet him in battle on land, assuming that he will not attack the town from the sea.
Although Lagatha's forces win the first engagement against Harald and Ivar's forces, they are ultimately defeated in the following engagement, largely due to the intervention of Rollo's contribution of Frankish troops to Ivar's cause. During the fighting, Lagatha confronts Astrid, who forces her lover to murder her as she does not want to give birth to her child. The combined psychological trauma of Astrid's death and her defeat at Harad's forces ultimately breaks Lagatha, as seen with her blonde hair turning white.
Lagertha is a brave and ferocious shield-maiden with an unbreakable code of honor. She is also ruthless, bloodthirsty, fiercely ambitious, and desires to rule. She is a doting parent and continues to be very affectionate and motherly with Bjorn even after he reaches early adulthood. She is fiercely protective of those who can’t stand up for themselves, particularly unarmed women, children, and women with a child in need of help. She is especially protective of women from would-be rapists or abusive husbands.
Lagertha can also be impulsive, prone to poor decision making, and lacking tact and diplomacy. She frequently acts and says things on impulse or for short term gratification without considering the long-term implications and consequences. Her direct bluntness and lack of tact tends to rub salt in the wounds that her actions created. For example, she inadvertently destroys Ragnar’s alibi he was using to protect her when Earl Haraldson put them on trial for the death of Knut. Upon returning to Kattegat after murdering Knut during the raid, Ragnar tries to spare his wife any punishment by taking the fall for the murder. He is arrested and tries to argue before a court that he had to kill Knut for trying to rape his lawful wife. His alibi seems to be working, until Lagertha is provoked by Haraldson into blurting out the truth to save Ragnar. In doing so she basically ruins his case and makes them both look like liars. Had Rollo not come forward and corroborated Ragnar’s version of events, they both would likely have been found guilty. Her knee-jerk reaction to Ragnar taking a second wife leads her to becoming trapped in an abusive relationship with Earl Sigvard, who is apparently insane. This eventually culminates in her murdering Sigvard in front of the entire Hall after one abuse too many. Whatever Sigvard’s faults, Lagertha murdered Hedeby’s chieftain and her lawful husband in front of his oath-sworn warriors. In an honor-bound society that takes fidelity to its lord quite seriously, Lagertha was always going to be unpopular after that. All this eventually culminates in her being rather easily usurped as Earl of Hedeby. She sleeps with King Ecbert then blows him off by telling him how little she thinks of his character. She insists on holding bloody pagan rituals in front of fundamentalist Christians in the Wessex settlement. And most crucially, she kills Aslaug rather than accepting Aslaug’s surrender after conquering Kattegat. However, given the norms of Norse society, Lagertha couldn’t leave Aslaug alive to act as a focus point for any resistance or future revenge plots. Her murder of Aslaug leads to the Kattegat Civil War and the deaths of many Vikings, including Astrid and other close friends. Many of the situations Lagertha finds herself in, or that result from her actions, might have been resolved or mitigated if Lagertha had the ability to smooth the feathers she ruffles or was able to win people over. Essentially, Lagertha is exactly the sort of person you want on your side in battle, but far down the list of people you want handling any kind of diplomacy or long-term planning. And as it happens, not thinking things through contributes to her getting murdered when she decides to die back in Kattegat despite being seriously wounded.
Lagertha also tends to be hypocritical. While she would refuse to admit it, Ivar correctly points out the only reason she conquered Kattegat was out of ambition. On the other hand, the first step anybody takes in climbing the political ladder in Norway is to seize Kattegat. She calls Ivar a would-be usurper, never mind the fact that she is one herself since she took the throne by force from Aslaug. Lagertha likes to speak of Ragnar’s grand dream of a better future where their people can become peaceful farmers in a far-off Scandinavian colony. But when Floki shows up and has found an uninhabited land awaiting settlement, Lagertha forbids him from recruiting because she says she needs every man possible to fight King Harald and keep her power over Kattegat. Finally, despite her hatred of rape, she has no problem committing it herself by raping Harald when he was bound and unable to stop her in an act of revenge against him for the deaths of her loyal soldiers.
Lagertha experiences quite a few traumatic events. She loses her daughter to plague while her husband has an affair. She has several miscarriages. She is seriously wounded in battle several times. And she is gang beaten in her bedroom. Through it all she manages to keep herself together. But when Ivar and Harald defeat her and Bjorn in battle, during which she sees Hvitserk kill Guthrum, a pregnant Astrid run into her sword, and her lover Bishop Heahmund die, she can’t take it anymore and finally snaps. Soon she is seriously shell-shocked and has severe PTSD.
Lagertha and Ragnar had a very loving relationship. Ragnar seems to value her opinions and was proud of her accomplishments as a shield-maiden. Lagertha fell madly in love with Ragnar after she watched as he killed a bear with his spear and strangled a hound to death with his bare hands in the same fight. However, when Ragnar becomes obsessed with the Seer's prophecy that he wold have many sons and Lagertha seems to have become barren, Ragnar becomes increasingly distant towards her. He cheats on her with Aslaug, and when Aslaug arrives in Kattegat pregnant, Lagertha is furious. When Ragnar suggests that he take Aslaug as a second wife, her feelings of betrayal are deepened and she divorces him and leaves Kattegat. But even after leaving Ragnar, she's still shown to have great affection for him. This might be because her second husband was simultaneously abusive and pathetic. They are also willing to work together to co-parent Bjorn, are on the same wavelength about safely retrieving Athelstan from Wessex, and she is openly affectionate with Ragnar's younger sons. While Lagertha isn't quite as forward thinking as Ragnar is, she supports his decisions almost instantaneously, clearly trusting and respecting his decisions inside and outside of battle. Lagertha greatly mourns Ragnar after his death, and it is hinted that she joins him in Valhalla.
Although not as strong as Ragnar's, Lagertha is consistently shown to have a good friendship with Athelstan. She even invited him to have sex with her and Ragnar. Unlike the other Vikings, Lagertha never displays any disdain for him after Season 1. She comes to view her former slave a real friend. And Athelstan seems to return the sentiment. She clearly trusts him enough to leave him with her children while she is away raiding with Ragnar. When Athelstan's survival is revealed in The Choice, she doesn't hesitate to follow Ragnar in retrieving him. Lagertha's wisdom and kindness earn Athelstan's respect and friendship.
Kalf and Lagertha had a love and hate relationship. Kalf was once her trusted advisor. She trusted him so much to the point of leaving him in command of Hedeby and to deal with Einar. But Kalf eventually betrayed her and usurped her throne, causing her to hate and want revenge on him. Things got worse when Ragnar instead of helping her, invites him to join the raid on Frankia. They fight together twice in the attacks on the bridge of Paris. After both saved the life of the other in different occasions. they start to gain respect for each other, to the point of Kalf revealing he always loved her. They have a conversation after Lagertha bathes. Kalf reveling wanting her with him in Hedeby. She accepts but at the same time swears she will kill him for having usurped her. When Lagertha was earl she asked Kalf why he didn't asked her hand in marriage, hinting she would have accepted. Kalf answered that he had nothing to offer. Eventually, she killed him on their wedding day, honoring her promise.
|“||Although you have made me happy and fulfilled, I have come to understand that the only person you truly care for is yourself.||”|
|“||Who knows, Ragnar, what the gods have in store for us. But this, I can never imagine. If you have gone to Heaven, then we will never meet again. And yet, I think Odin will ride like the wind, and rescue you, and take you to Valhalla, where you belong, my own sweet Ragnar. And there, there we shall meet again, and fight and drink and… love one another.||”|
|“||Power is dangerous. These are the words of the Gods. But that power, that danger, is everything. It lives in an army that will protect my people and my rule. My son, my legacy, has become the bravest of warriors. I listen silently to the ramblings of men. Those who dream of danger may awake to death. But life must be lived to the fullest before it is over. I embrace the idea of life and death. For I am not the one in charge of my fate. The gods have already written my story. Victory or Valhalla.||”|
–Lagertha, Vikings Season 4 Promo
|“||We have one life… so go and live it.||”|
|“||I advise you to keep your friends very close, for some of them will die only too soon. And the others… The others will betray you.||”|
|“||My heart was broken a long time ago.||”|
- As the reigning Earl of Hedeby, Lagertha's subjects and followers among the local population would be considered Jutish, given Hedeby's location in the Jutland Peninsula. There would also be Saxons present, as Hedeby was in the contemporary frontier zone with Frankish-occupied Saxony. Both Saxons and Jutes were among the Germanic tribes which took part in the migrations toward Britain in the four hundred years prior to the Viking Age.
- In The Legend of Ragnar Lothbrok, Lagertha, who was his first wife, gave birth to three children, son Fridleif and two unnamed daughters.
- Michael Hirst, creator and writer of the show, was quoted saying: "There's a feminist collective in New York who wrote to me a couple years ago and they said, 'We don't care how many of the male characters you kill off, but if you do anything to Lagertha, you're in trouble.' So I'm very careful about that warning."
- The character of Lagertha does not originate from Ragnar's saga but rather from the Gesta Danorum. Due to this Lagertha was never Bjorn's mother, Aslaug was. This by extension means Ragnar never had three wives, just two.
- The death of Lagertha has caused much anger among her fans, who say the formidable shield-maiden merited a better end.
|Season one appearances|
|Rites of Passage||Wrath of the Northmen||Dispossessed|
|Trial||Raid||Burial of the Dead|
|A King's Ransom||Sacrifice||All Change|
|Season two appearances|
|Brother's War||Invasion||Treachery||Eye For an Eye||Answers in Blood|
|Unforgiven||Blood Eagle||Boneless||The Choice||The Lord's Prayer|
|Season three appearances|
|Mercenary||The Wanderer||Warrior's Fate||Scarred||The Usurper|
|Born Again||Paris||To the Gates!||Breaking Point||The Dead|
|Season five appearances|
|The Departed Part 1||The Departed Part 2||Homeland||The Plan||The Prisoner|
|The Message||Full Moon||The Joke||A Simple Story||Moments of Vision|
|The Revelation||Murder Most Foul||A New God||The Lost Moment||Hell|
|The Buddha||The Most Terrible Thing||Baldur||What Happens in the Cave||Ragnarok|
|Season six appearances|
|New Beginnings||The Prophet||Ghosts, Gods, and Running Dogs||All The Prisoners||The Key|
|Death and the Serpent||The Ice Maiden||Valhalla Can Wait||Resurrection||The Best Laid Plans|
|King of Kings||All Change||The Signal||Lost Souls||All At Sea|
|The Final Straw||The Raft of the Medusa||It's Only Magic||The Lord Giveth||The Last Act|