This season of "Vikings" follows the sons of Ragnar Lothbrok as they vie for power and face new threats. Bjorn Ironside, Ragnar's eldest son, takes the throne of Kattegat, aiming to unite Norway. His brother, Ivar the Boneless, exiled and seeking revenge, allies with Prince Oleg of Kievan Rus' and plots his return. Meanwhile, their mother, the legendary shieldmaiden Lagertha, attempts to retire from battle but is repeatedly drawn back into conflict.

The central conflict escalates as Ivar and Oleg launch an invasion of Scandinavia, clashing with Bjorn and his allies. Key turning points include Lagertha's tragic death at the hands of her own son, Hvitserk, who mistakes her for Ivar. Bjorn is eventually fatally wounded on the battlefield during the invasion, and King Harald also perishes.

In the end, Ivar the Boneless dies in battle against the Saxons. Ubbe finds peace in a new world with Floki, while Queen Ingrid takes control of Kattegat. Hvitserk converts to Christianity, signifying the end of an era for Ragnar's sons.

Season 6 of Vikings covers episodes 1-20. Here's everything that happened:

Season 6, Episode 1: New Beginnings - Bjorn assumes the throne of Kattegat, while Lagertha decides to retire and live as a farmer. Meanwhile, Ivar, exiled and captured by Prince Oleg of Kievan Rus', finds a new, dangerous ally. Lagertha buries her sword, signaling her retirement from battle, and Ivar begins to plot his return to power with Oleg. The episode concludes with Bjorn facing the challenge of leadership and Ivar setting his sights on Kattegat once more.

Season 6, Episode 2: The Prophet - Messengers bring Bjorn a dilemma while Lagertha finds peace, though danger looms. In Kievan Rus', Ivar is captured by Prince Oleg, who murders his own brother to secure guardianship of Prince Igor. Oleg then imprisons Dir, forcing him to allow their passage to Scandinavia.

Season 6, Episode 3: Ghosts, Gods and Running Dogs - Lagertha is forced to abandon her peaceful retirement after raiders attack a nearby village, leading her to unearthed her sword and return to her role as a shieldmaiden. Meanwhile, Bjorn's attempt to rescue Harald from King Olaf ends in a fiery ambush. In Kievan Rus', Ivar grows increasingly wary of Prince Oleg's volatile nature and his brutal treatment of his brother, Dir, whom Oleg mutilates and imprisons like a dog. Ubbe plans a Silk Road expedition for Hvitserk, who is haunted by visions of his deceased lover.

Season 6, Episode 4: All the Prisoners - Lagertha, forced out of retirement, leads a defense against attackers but suffers tragic losses. King Olaf proposes uniting Norway under Bjorn, who is strategizing after a setback. In Rus, Ivar plots with Igor against Oleg, who plans an invasion of Scandinavia. Bjorn's attempt to free Harald leads to a proposal for a unified Norway, with Bjorn as king. The episode concludes with Lagertha's village devastated and Hvitserk struggling with his demons, highlighting the ongoing cycle of violence.

Season 6, Episode 5: The Key - The election for the King of all Norway begins, with Olaf surprisingly voting for Bjorn. In Kiev, Ivar is stunned to encounter a woman who looks identical to his deceased wife, Freydis. Meanwhile, Lagertha's village faces another attack, and she admits to Gunnhild that she can never be the same after the loss of her grandson. Ivar and Prince Igor plot against Oleg, leading to a confrontation.

Season 6, Episode 6: Death and the Serpent - Bjorn struggles after losing the election for King of Norway. Lagertha successfully defends her village against bandits, but is tragically slain by her hallucinating son, Hvitserk, who mistakes her for Ivar. Meanwhile, in Kievan Rus', Oleg marries Katia in front of a disturbed Ivar, who is denied permission to leave.

Season 6, Episode 7: The Ice Maiden - Bjorn returns to Kattegat to find the funeral of his mother, Lagertha, underway. In Kiev, Ivar and Igor receive news about Prince Dir, while Harald exacts revenge on Olaf. The episode concludes with Lagertha's visually stunning funeral, where she is laid to rest on a ship and symbolically journeys to Valhalla, finding peace beside Ragnar. Hvitserk's paranoia leads to Lagertha's accidental death, and Torvi's offer to be a human sacrifice is refused due to her pregnancy.

Season 6, Episode 8: Valhalla Can Wait - Bjorn grapples with the confession of Hvitserk, who admits to killing Lagertha, believing it was divine vengeance. Bjorn ultimately exiles Hvitserk to die in the winter rather than execute him. Meanwhile, Ubbe and Torvi depart for Iceland, and Oleg's invasion plans for Norway begin with a brutal raid. The episode concludes with Harald facing an unexpected threat.

Season 6, Episode 9: Resurrection - Bjorn marries Ingrid, upsetting Gunnhild, while in Iceland, Torvi survives childbirth. Erik's scouting mission reveals Ivar is leading a Rus party, prompting Bjorn to seek an alliance with Harald. Ivar and Hvitserk reunite, and Hvitserk learns of Oleg's plan to eliminate all pagan leaders. The episode concludes with Bjorn facing the difficult decision of whether to trust Harald and leave Kattegat vulnerable.

Season 6, Episode 10: The Best Laid Plans - Ivar and Prince Oleg's invasion of Scandinavia begins, while King Harald and Bjorn prepare defenses. Despite their efforts, the Rus forces overwhelm the Scandinavian armies. Bjorn Ironside is fatally wounded on the battlefield, and King Harald lies dying. The episode concludes with Oleg and the Rus celebrating their victory, marking a significant shift in power.

Season 6, Episode 11: King of Kings - In Iceland, Ubbe confronts Kjetill about his actions. Meanwhile, back in Norway, King Olaf is burned alive by Prince Oleg's forces. Bjorn, though grievously wounded, rallies his troops for a final stand, but ultimately succumbs to his injuries, achieving a glorious death as the "King of Kings." The episode concludes with Harald's escape and Gunnhild vowing to uphold Bjorn's legacy.

Season 6, Episode 12: All Change - Following Bjorn's death, Prince Oleg isolates Ivar in Kiev, while Dir plots to overthrow Oleg. In Kattegat, Ingrid reveals she is pregnant with Bjorn's child, complicating the succession. Meanwhile, Ubbe and his settlers depart Iceland in search of the Golden Land, leaving behind the political turmoil.

Season 6, Episode 13: The Signal - In Kattegat, Gunnhild and Ingrid vie for the throne, with Ingrid revealing she's carrying Bjorn's child. Meanwhile, in Kiev, Ivar, Hvitserk, and Katia execute a daring plan to free Prince Igor from Oleg's grasp. The episode concludes on a cliffhanger as Oleg realizes Igor is missing, while Ubbe's voyage is hit by a devastating storm that sweeps his child overboard.

Season 6, Episode 14: Lost Souls - Prince Igor is welcomed in Novgorod, while Oleg plots revenge. Ubbe's settlers find a harsh, unwelcoming land in Iceland, leading to tension. In Kattegat, Gunnhild and Ingrid agree to marry Harald, solidifying his claim to the throne. Erik attempts to assassinate Harald but is thwarted when Erik decapitates his co-conspirator, securing Harald's favor.

Season 6, Episode 15: All At Sea - In Greenland, Kjetill's descent into madness leads to bloodshed, forcing Ubbe and others to flee by boat, abandoning their settlement. Meanwhile, in Kiev, Ivar manipulates Igor into killing his uncle Oleg, ending Oleg's tyrannical rule. Gunnhild chooses a symbolic death, diving into the sea to reunite with Bjorn in Valhalla.

Season 6, Episode 16: The Final Straw - Ivar and Hvitserk return to Kattegat, finding King Harald on the throne. Ubbe's expedition faces dire conditions at sea, with dwindling supplies and baby Ragnar weakening, pushing Ubbe to a breaking point. Meanwhile, King Harald attempts to unite Kattegat by advocating for forgiveness for Ivar and Hvitserk, despite their past actions. The episode concludes with Ubbe's faith severely tested by the harsh realities of his voyage.

Season 6, Episode 17: The Raft of Medusa - In Wessex, Ivar and Hvitserk achieve victory against King Alfred's forces, who retreat. Meanwhile, in Kattegat, Ingrid uses witchcraft to blind Erik, seizing control. Ubbe and Torvi's arduous voyage culminates in the sighting of a new land, offering a glimmer of hope amidst their suffering.

Season 6, Episode 18: It's Only Magic - Ubbe and his settlers discover a new land, only to find it already inhabited. In Wessex, King Alfred prepares his forces for battle, but is struck by a mysterious illness. Meanwhile, in Kattegat, Erik realizes Ingrid's sorcery and plots against her. Ivar is warned of his impending doom, while Alfred rallies his troops with a powerful speech, ultimately facing the Vikings in a climactic confrontation.

Season 6, Episode 19: The Lord Giveth… - Ivar's cunning trap cripples many Saxon soldiers, leading to a chaotic battle where King Harald is killed. Meanwhile, Ubbe engages in diplomacy in the new land, and Ingrid consolidates her power in Kattegat. The episode concludes with Ubbe discovering Floki alive in a treehouse.

Season 6, Episode 20: The Last Act - The epic saga concludes with Ivar the Boneless dying in battle against the Saxons. Meanwhile, Ubbe finds peace in the new world with Floki. Queen Ingrid assumes control of Kattegat, and Hvitserk converts to Christianity, marking the end of the sons of Ragnar's story.