The season, consisting of 20 episodes, was split into two ten-episode parts.
Part I Edit
Season three culminated with the extraordinary battle in Paris, where Ragnar seized victory from the jaws of defeat – but still returns to Kattegat dangerously ill. Thoughts of his death galvanize the forces who seek to succeed him as king, including his wife Queen Aslaug and his oldest son, Bjorn. Meanwhile, Lagertha continues power struggles with her calculating, former second in command, Kalf. Rollo betrays his Vikings heritage by remaining in Frankia and Floki is seized for his brutal actions to the Christian priest Athelstan.
Part II Edit
In the midseason premiere, Ragnar’s reappearance in Kattegat triggers a chain of events no one – except the Seer – could have ever imagined. He unexpectedly arrives home to see what has become of his sons.
Main Cast Edit
- Travis Fimmel as King Ragnar Lothbrok (16 episodes)
- Katheryn Winnick as Queen Regnant Lagertha/Earl Ingstad (18 episodes)
- Clive Standen as Duke Rollo (14 episodes)
- Gustaf Skarsgård as Floki (19 episodes)
- Alexander Ludwig as Bjorn (19 episodes)
- Alyssa Sutherland as Queen Consort Aslaug (15 episodes)
- Ben Robson as Earl Kalf (4 episodes)
- Lothaire Bluteau as Emperor Charles (8 episodes)
- John Kavanagh as The Seer (9 episodes) and Pope Leo IV ("Death All 'Round")
- Peter Franzén as King Harald "Finehair" (14 episodes)
- Jasper Pääkkönen as Halfdan "The Black" (13 episodes)
- Moe Dunford as Prince Aethelwulf (7 episodes + 6 as recurring)
- Kevin Durand as Harbard (3 episodes)
- Alex Høgh as Ivar (9 episodes + 1 as guest)
- Marco Ilsø as Hvitserk (7 episodes + 1 as guest)
- David Lindström as Sigurd (9 episodes + 1 as guest)
- Jordan Patrick Smith as Ubbe (8 episodes + 1 as guest)
- Linus Roache as King Ecbert (16 episodes)
- Jonathan Rhys Meyers as Bishop Heahmund ("The Reckoning")
Special Guest Cast Edit
Recurring Cast Edit
- Maude Hirst as Helga (16 episodes)
- Jennie Jacques as Princess Judith (16 episodes)
- Georgia Hirst as Torvi (15 episodes)
- Morgane Polanski as Princess Gisla (12 episodes)
- Josefin Asplund as Astrid (9 episodes)
- Ida Marie Nielsen as Margrethe (8 episodes)
- Owen Roe as Count Odo (7 episodes)
- Dianne Doan as Yidu (7 episodes)
- Edvin Endre as Erlendur (6 episodes)
- Ivan Kaye as King Aelle (6 episodes)
- Amy Bailey as Queen Kwenthrith (5 episodes)
- Seán T. Ó Meallaigh as Father Prudentius (5 episodes)
- George Blagden as Athelstan (5 episodes)
- Nathan O'Toole as Young Bjorn (3 episodes)
- Morgan O'Sullivan: executive producer.
- Sheila Hockin: executive producer.
- Sherry Marsh: executive producer.
- Alan Gasmer: executive producer.
- James Flynn: executive producer.
- John Weber: executive producer.
- Michael Hirst: creator/writer/executive producer.
- Keith Thompson: producer (episodes 1, 2, 3, 4, 5, 6, 7, 8, 17, 18, 19, and 20).
- Sanne Wohlenberg: producer (9, 10, 11, 12, 13, 14, 15, and 16).
- Bill Goddard: co-producer.
- Séamus McInerney: co-producer.
- Pj Dillon: director of photography (episodes 1, 2, 3, 4, 5, 6, 7, 8, 17, 18, 19, and 20).
- Owen McPolin: director of photography (episodes 9, 10, 11, 12, 13, 14, 15, and 16).
- Mark Geraghty: production designer.
- Aaron Marshall: editor (episodes 1, 4, 7, 15, and 18).
- Christopher Donaldson: editor (episodes 2, 5, and 8).
- Tad Seaborn: editor (episodes 3, 6, 9, 11, 13, 16, and 19).
- Don Cassidy: editor (episodes 10, 12, 14, 17, and 20).
- Trevor Morris: composer.
- Franklin Henson: stunt action design.
- Richard Ryan: stunt action design.
- Dominic Remane: visual effects supervisor.
- Joan Bergin: costume designer.
- Frank Moiselle: casting director.
- Nuala Moiselle: casting director.
- Ciarán Donnelly: episodes 1, 2, 3, 15, and 16.
- Helen Shaver: episodes 4 and 5.
- Ken Girotti: episodes 6, 7, and 8.
- Jeff Woolnough: episodes 9, 10, 17 and 18.
- Daniel Grou: episodes 11 and 12.
- Sarah Harding: episodes 13 and 14.
- Ben Bolt: episodes 19 and 20.
- See also: Episodes
|4.01||30||A Good Treason||February 18, 2016|
|As Ragnar lies in his sick bed in Kattegat, events unfold beyond his control; Bjorn orders the arrest of Floki for Athelstan's murder; Rollo betrays his Viking supporters to strengthen his position; Kalf announces joint Earldom with Lagertha.|
|4.02||31||Kill the Queen||February 25, 2016|
|Ragnar and Floki are still at odds; Rollo makes great attempts to win over his new bride, Princess Gisla; Bjorn's survival skills are put to the test; King Ecbert sets the task for his son Aethelwulf to rescue Queen Kwenthrith.|
|4.03||32||Mercy||March 3, 2016|
|Ragnar informs Floki of a heavy price he has paid for his actions; Rollo finds an unlikely ally in Count Odo; Bjorn has to fight a fierce opponent in the wilderness.|
|4.04||33||Yol||March 10, 2016|
|A Norwegian king and Bjorn, who is accompanied by a new partner, will get welcomed to the Great Hall in Kattegat. King Aelle will end up arriving at Wessex for Christmas and will be unimpressed with the development of family relations. Meanwhile, in Paris, Rollo’s future is going to depend on whether he can win over his new bride, as a papal delegation arrives to arrange a divorce.|
|4.05||34||Promised||March 17, 2016|
|There's an air of betrayal as those whom Odo trusts plot against him; Ecbert agrees to support Kwenthrith in Mercia; Pregnancy brings happiness to Lagertha and Kalf and a marriage is arranged.|
|4.06||35||What Might Have Been||March 24, 2016|
|At the Thing in Kattegat, Ragnar reveals his plan to raid Paris again, and, although the fleet is storm-tossed as it sets out, the challenge lies in France, where Rollo awaits. Meanwhile, Ecbert dispatches Aethelwulf and Alfred on a pilgrimage to Rome.|
|4.07||36||The Profit and the Loss||March 31, 2016|
|In England, King Ecbert schemes to secure the crown of Mercia, while outside Paris, a considerable force of Vikings attack Rollo's defenses. Also, the mysterious wanderer Harbard returns to Kattegat and causes a stir among the women.|
|4.08||37||Portage||April 07, 2016|
|Ragnar’s leadership is going to get called into question after their defeat, evacuation and retreat down-river. Although, he will have a plan that he is going to keep under wraps.Rollo and Gisla are going to have information that will strengthen Rollo’s position at the French court, while Count Odo will be slow to identify his true enemies, which could have serious consequences.|
|4.09||38||Death All 'Round||April 14, 2016|
|As they near Paris, the Vikings relaunch their boats, but this time they bear interesting structures made by Floki; Aethelwulf and Alfred arrive in Rome, where honors are bestowed by Pope Leo, but in Wessex, relations are less than cordial between King Ecbert and a disgruntled King Aelle.|
|4.10||39||The Last Ship||April 21, 2016|
|A fierce battle between the Vikings and the French eventually comes down to Ragnar against Rollo and the outcome seals the fates of the two brothers.|
|4.11||40||The Outsider||November 30, 2016|
|Ragnar arrives home unexpectedly to see what has become of his sons and to handle unfinished business with King Ecbert; Lagertha plans a power play; Bjorn prepares to explore the Mediterranean in a sleek, new boat built for him by Floki.|
|4.12||41||The Vision||December 07, 2016|
|The Kattegat locals chide Ragnar that the gods have deserted him as he struggles to crew his voyage to Wessex. It’s Bjorn who has charisma now as he prepares to fulfill his long-held dream to explore the Mediterranean in a sleek new boat built for him by Floki. By contrast, Ragnar must accept weathered boats and a crew he has bribed but when Aslaug foresees that the fleet will be lost in a vicious storm her warnings go un-heeded by Ragnar and her precious son, Ivar.|
|4.13||42||Two Journeys||December 14, 2016|
|Ragnar’s fleet is shipwrecked and washes up on the Wessex coast, but without enough survivors to form a credible force, Ragnar and Ivar have a difficult decision to make. Rollo meets his Viking comrades again and can’t resist the urge to join Bjorn’s voyage, risking his marriage and his new Frankish identity. Ragnar too is taking a risk as he carries Ivar towards the Royal Villa in Wessex – throwing himself and his son upon the mercy of King Ecbert.|
|4.14||43||In the Uncertain Hour Before the Morning||December 21, 2016|
|Lagertha fulfills her long-held ambition to take Kattegat; King Ecbert must decide whether to hand his friend, Ragnar, over to King Aelle, who has sworn revenge on him.|
|4.15||44||All His Angels||December 28, 2016|
|Ragnar and Ivar plot against the Saxons and reach a new level of understanding. King Aelle can not hide his pleasure when Ragnar arrives in a cage and shows no mercy.|
|4.16||45||Crossings||January 04, 2017|
|Bjorn's fleet sails onward and launches a surprise attack; back in Kattegat, Lagertha continues in her quest for power.|
|4.17||46||The Great Army||January 11, 2017|
|The Viking army begins to gather in Kattegat; Lagertha must remain vigilant in the absence of her son, Bjorn.|
|4.18||47||Revenge||January 18, 2017|
|Ragnar's plan comes to fruition; the Viking army lands on the coast of Northumbria.|
|4.19||48||On the Eve||January 25, 2017|
|The Viking army causes panic in the English countryside as King Ecbert and Aethelwulf plan the defense of the realm.|
|4.20||49||The Reckoning||February 01, 2017|
|Prince Aethelwulf finds himself subject to the Vikings' battle master plan; Ecbert remains behind with a plan of his own.|