Season 5 of Vikings was the first time of premise of the fifth season differs from the previous four after the departure of Travis Fimmel as Ragnar, and it follows the adventures of his sons. The season, consisting of 20 episodes, was split into two ten-episode parts just like the previous season, with the first part airing from November 29, 2017 to January 24, 2018. It was announced from San Diego Comic-Con International 2018 that the mid-season will return on November 28, 2019 along with an exclusive trailer that was unveiled to nearly 5,000 fans during the Vikings cast panel held at Ballroom 20 on July 20 that year. The second part of Season 5 concluded on January 30, 2019.
In Norway, in the wake of the death of King Ragnar and his son Sigurd, the sons of Ragnar are in civil war. Ivar claims the title of king over the kingdom of Kattegat, supported by Hvitserk and king Harald. Ubbe sides with Lagertha against their alliance. In England, King Aethelwulf and bishop Heahmund wage war against the Nordic invaders. In the Mediterranean, Bjorn follows his destiny as he and Halfdan explores northern Africa. On the Atlantic, Floki makes a discovery that will change the world of the Norsemen forever.
In Norway, Lagertha's army is on the brink of being routed from Kattegat, with Ivar prepared to captured the city and claim his revenge. In England, after the passing of King Aethelwulf, Aethelred rallied the Lords behind his half-brother Alfred and proclaimed him King of Wessex. In Iceland, the feud between the families of Kjetill and Eyvind escalate to the point where each of their sons are killed. Determined to prevent further bloodshed, Floki offers himself as a sacrifice.
Season five returns on November 28 with the arrival of a legendary Viking, the famous Duke Rollo (Clive Standen), who causes further upheaval in a Kattegat still reeling from Ivar the Boneless becoming its King. As Bjorn (Alexander Ludwig) and Lagertha flee Ivar’s murderous forces with Bishop Heahmund (Jonathan Rhys Meyers), Ivar’s tyrannical reign over Scandinavia ushers in a new Dark Age, the likes of which have never been seen. Ultimately, Ivar’s reign will not go unchallenged by the sons of Ragnar and old enemies will become allies to defeat the despot who has declared himself a God on earth. Meanwhile in Iceland, Floki (Gustaf Skarsgård) battles the elements, and his own settlers’ desire for revenge, to forge a Viking colony on the beautiful and desolate landscape.
An Irish-Canadian co-production presented by Metro-Goldwyn-Mayer, the fifth season of Vikings was developed and produced by TM Productions and Take 5 Productions. Morgan O'Sullivan, Sheila Hockin, Sherry Marsh, Alan Gasmer, James Flynn, John Weber, and Michael Hirst are credited as executive producers. This season was produced by Keith Thompson for the first four and last four episodes, and Liz Gill for the fifth to sixteenth episodes. Bill Goddard and Séamus McInerney act as co-producers.
The production team for this season includes casting directors Frank and Nuala Moiselle, costume designer Susan O'Connor Cave, visual effects supervisor Dominic Remane, stunt action designer Richard Ryan, composer Trevor Morris, production designer Mark Geraghty, editors Aaron Marshall for the first, third, fifth, tenth, fourteenth, seventeenth and twentieth episodes, Tad Seaborn for the second, fourth, sixth, eighth, thirteenth, sixteenth and nineteenth episodes, Michele Conroy for the seventh, ninth and eleventh episodes, Dan Briceno for the twelfth episode, and Don Cassidy for the fifteenth and eighteenth episodes and cinematographers PJ Dillon for the first and second episodes, Peter Robertson for the third, fourth, and seventh to sixteenth episodes, Suzie Lavelle for the fifth, sixth, seventeenth and eighteenth episodes, and Owen McPolin for the nineteenth and twentieth episodes.
- Katheryn Winnick as Queen Lagertha
- Gustaf Skarsgård as Floki
- Alexander Ludwig as Prince Bjorn "Ironside"
- John Kavanagh as The Seer
- Peter Franzén as King Harald "Finehair"
- Jasper Pääkkönen as Halfdan the Black
- Moe Dunford as King Aethelwulf
- Alex Høgh as Prince Ivar the Boneless
- Marco Ilsø as Prince Hvitserk
- Jordan Patrick Smith as Prince Ubbe
- Jonathan Rhys Meyers as Bishop Heahmund
Special Appearance By
- Jennie Jacques as Queen Judith
- Georgia Hirst as Torvi
- Josefin Asplund as Astrid
- Ida Marie Nielsen as Margrethe
- Frankie McCafferty as Sinric
- Adam Copeland as Kjetill "Flatnose"
- Kris Holden-Reid as Eyvind 
- Ferdia Walsh-Peelo as King Alfred
- Darren Cahill as Prince Aethelred
- Steven Berkoff as Olaf the Stout
- Karima McAdams as Kassia
- Roisin Murphy as Queen Elsewith
- Ragga Ragnars as Gunnhild
- Dean Ridge as Magnus
- Michael Hirst (20 Episodes)
- David Wellington (4 episodes)
- Ciaran Donnelly (5 episodes)
- Steve Saint Leger (5 episodes)
- Jeff Woolnough (2 episodes)
- Daniel Grou (2 episodes)
- Helen Shaver (2 episodes)
- See also: Episodes
|5.01||50||"The Departed Part 1"||November 29, 2017|
|Tensions mount between the sons of Ragnar Lothbrok; with King Aethelwulf and his family still in hiding, Heahmund, the warrior bishop, rallies the Saxons to defend the Realm, as the Great Army moves to take York.|
|5.02||51||"The Departed Part 2"||November 29, 2017|
|Ivar is determined to lead the Great Army as the Vikings establish their stronghold in York; in Kattegat, Lagertha misjudges King Harald and pays a heavy price; Floki arrives at a mysterious land.|
|5.03||52||"Homeland"||December 6, 2017|
|Celebrations are cut short in the aftermath of the battle at York; Ragnar Lothbrok's sons are pitted against each other as tensions reach an all-time high, and each one is forced to choose a side.|
|5.04||53||"The Plan"||December 13, 2017|
|Guided by Bishop Heahmund's visions, the Saxons devise a battle plan; Ivar the Boneless strategizes as the Vikings undergo increasing pressure; Bjorn Ironside finds himself in a new territory and must convince the local commander he is a trader.|
|5.05||54||"The Prisoner"||December 20, 2017|
|Ivar meets his match in Bishop Heahmund; Floki returns to Kattegat; Bjorn receives a lavish welcome in North Africa.|
|5.06||55||"The Message"||December 27, 2017|
|Lagertha is betrayed, and Bjorn must find a way to support the distraught queen; Floki and his settlers arrive in a new land, but it is far from what they expected.|
|5.07||56||"Full Moon"||January 3, 2018|
|Bjorn returns to Kattegat to learn that an attack will take place during the next full moon; Ivar must decide if he can place his trust in a former enemy on the battlefield.|
|5.08||57||"The Joke"||January 10, 2018|
|The battle for Kattegat begins; as the two armies line up to fight, the Great Heathen Army must decide between a final plea for peace or all-out war; Floki faces discord among the settlers.|
|5.09||58||"A Simple Story"||January 17, 2018|
|The army leaders consider their options in the aftermath of the battle; in Floki's camp, all hopes of binding the community together are dashed as tragedy unfolds.|
|5.10||59||"Moments of Vision"||January 24, 2018|
|A sense of doom looms over Kattegat as bloodshed ensues; the defeated army flees in the face of the victors, and a legendary warrior makes his way home.|
|5.11||60||"The Revelation"||November 28, 2018|
|Legendary Viking Duke Rollo arrives, causing further upheaval in a Kattegat still reeling from Ivar the Boneless becoming its king; Floki battles the elements in Iceland, and his own settlers' desire for revenge, to forge a colony.|
|5.12||61||"Murder Most Foul"||December 5, 2018|
|Bjorn, Lagertha and Ubbe face an uncertain fate as Heahmund's loyalty is tested; Floki fights to understand the will of the gods in Iceland; Ivar may have met his match in Kattegat.|
|5.13||62||"A New God"||December 12, 2018|
|Heahmund must convince King Alfred that his actions are in defense of the crown; Ubbe and Torvi strengthen the position of the Vikings, but not all in the Viking camp support their strategy; another settler disappears in Iceland.|
|5.14||63||"The Lost Moment"||December 19, 2018|
|As the celebrations for Ivar continue in Kattegat, grief hits Iceland and Floki must now make a fated decision; Harald's army approaches Wessex; a conspiracy grows against King Alfred.|
|5.15||64||"Hell"||December 26, 2018|
|Bishop Heahmund is wracked with guilt as he fights to renounce his passions; Viking clashes with Saxon on the battlefield, leaving a key figure lost in the balance.|
|5.16||65||"The Buddha"||January 2, 2019|
|Bjorn achieves one of Ragnar's dreams; Ivar hatches a new plan in Kattegat, while preparing for a divine arrival; a settler in Iceland returns in a terrible state; King Alfred faces his greatest threat yet|
|5.17||66||"The Most Terrible Thing"||January 9, 2019|
|An unexpected turn amongst the settlers leaves Floki powerless. King Alfred confronts Judith. In York, Bjorn must strike a deal with Harald. Wessex is once again threatened by a Viking force, but who will lead the Saxon army to defend the Realm?|
|5.18||67||"Baldur"||January 16, 2019|
|Hvitserk is severely tested; Floki makes an amazing discovery; Freydis gives Ivar a surprise; Ubbe negotiates with the three Danish kings who have massed their armies in Reading, but the negotiations may have a perilous outcome.|
|5.19||68||"What Happens in the Cave"||January 23, 2019|
|Ubbe is forced into hand-to-hand combat. Floki reaches new depths and is met by a shocking sight. Bjorn sets off for Scandinavia with an old rival.|
|5.20||69||"Ragnarok"||January 30, 2019|
|A new battle for Kattegat is on and only the gods know who will emerge victorious.|
- Bishop Cynebert
- Lord Denewulf
- King Aethelwulf
- King Svase
- Princess Snaefrid
- Lord Cuthred
- The Seer
- Bishop Heahmund
- Prince Aethelred
- Queen Judith
- King Frodo
- Katheryn Winnick, Gustaf Skarsgård, Alexander Ludwig, John Kavanagh, Peter Franzén, Jasper Pääkkönen, Moe Dunford and Jonathan Rhys Meyers are only credited for their respective episode appearances.
- Season 5 marked the last for series regulars Jasper Pääkkonen, Moe Dunford and Jonathan Rhys Meyers.
- This is the only season not to feature new series regulars.