Torvi, tired of Erlendur's abuse, accepts Bjorn's offer to follow him to Kattegat. As she was preparing to leave with Guthrum, Erlendur tells her that it is his right to keep Guthrum with him. Torvi decides to leave him in Hedeby under the care of Lagertha, who promises to keep him safe. Erlendur uses Guthrum as a hostage, threatening to kill him if Torvi does not act as his spy on Ragnar's family.
Not long after, Lagertha is praying on Kalf's tomb. She tells Guthrum that she has to leave for the raid on Paris again, and that he should keep his friends close while she is away because many die before their time and the rest would eventually betray him. During the Second Siege of Paris, Erlendur tries to force Torvi to assassinate Bjorn by threatening to kill Guthrum. Instead, Torvi kills Erlendur, saving Bjorn and freeing Guthrum.
Ten years later, Guthrum is living with Torvi, Bjorn, and his two half-siblings Hali and Asa in Kattegat. Guthrum is loyal to Bjorn, despite Ragnar killing his father. He is with Bjorn and Torvi watching King Harald's arrival in Kattegat.
Guthrum has grown into a young man with a will of his own. Initially interested in joining Floki's expedition to Iceland, he is chosen as chief of the new settlement along with Eyvind, Ketjill, and Aud. Upon realizing that he can't go to Valhalla and meet his father in a land with no war, he betrays Floki and the expedition.
Guthrum fights in the Kattegat Civil War on the side of his mother and Bjorn. In the Second Battle for the Kingdom of Kattegat, Guthrum comes face-to-face with Hvitserk. He is immediately outmatched and clearly the weaker opponent. Torvi notices her son struggling and attempts to rush to his aid. But it is too late. He is thrown to the ground and killed by Hvitserk with an axe to the chest as Torvi screams in horror. Lagertha witnesses the whole ordeal. Torvi throws her shield to the side and bashed her sword into Hvitserk who does not appear to be aware of what he has done. As the fighting grows around them, they are separated. She tries to get to Guthrum's body, but the fighting doesn't let her. Yelling in rage and grief, Torvi grabs her shield and sword and returns to the battle.
As the last of his father's house, with his death, Jarl Borg's dynasty is completely extinguished.
Hvitserk is implied to be the same as the historical figure Guthrum after Hvitserk is baptized as Athelstan and made a "Saxon prince" by King Alfred the Great.
Guthrum listens to Lagertha.
|Season three appearances|
|Mercenary||The Wanderer||Warrior's Fate||Scarred||The Usurper|
|Born Again||Paris||To the Gates!||Breaking Point||The Dead|
|Season four appearances|
|A Good Treason||Kill the Queen||Mercy||Yol||Promised|
|What Might Have Been||The Profit and the Loss||Portage||Death All 'Round||The Last Ship|
|The Outsider||The Vision||Two Journeys||In the Uncertain Hour Before the Morning||All His Angels|
|Crossings||The Great Army||Revenge||On the Eve||The Reckoning|
|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|