Season synopsis
Contains spoilers for this season and earlier seasons.
After Ecbert’s death, Ragnar’s sons divide over what to do with the kingdom and one another. Ivar’s killing of Sigurd has intensified the brothers’ rivalry while Lagertha holds Kattegat. Bjorn travels through the Mediterranean, while Floki leads settlers to Iceland in search of a new home. In England, Ubbe and Hvitserk pursue different approaches to the Saxons, and the Great Army’s campaign becomes entangled with rivalry between Ivar, Lagertha and Harald.
Ivar defeats Lagertha’s forces, takes Kattegat and crowns himself king. Rollo offers Lagertha and Bjorn refuge in Francia, claiming Bjorn is his son, but Bjorn refuses and joins Ubbe in England. Hvitserk initially stays with Ivar, even as Ivar’s violence unsettles him. Ubbe and Torvi accept Alfred’s request to convert, and Alfred later grants them land in East Anglia. Floki’s Iceland settlement fractures through hunger and murder; searching a cave, he finds a Christian cross before a collapse traps him.
Returning from England, Bjorn allies with Harald to challenge Ivar. Hvitserk changes sides and joins Bjorn, Harald and Olaf in the assault on Kattegat. Harald saves Bjorn during the battle, while Freydis’s betrayal is exposed; Ivar kills her, then escapes before the victors reach his hall. Lagertha names Bjorn king, though his reign begins amid civil war. The season closes with Ivar fleeing east, Floki’s fate uncertain after the cave collapse, and Alfred’s East Anglia grant giving Ubbe and Torvi a concrete settlement.