Season 3 of The Last Kingdom was announced by Netflix on 4 April 2018. The season premiered on 19 November 2018 and consisted of ten episodes. Production began on 23 October 2017 in Budapest and concluded in May 2018. It roughly adapted the plots of the "The Burning Land" and "Death of Kings", the fifth and sixth novels in Bernard Cornwell's The Saxon Stories.
Uhtred turns his attention to Æthelflæd's plight. Alfred forces Edward to face his duty. Ragnar's army marches but traitors emerge from within.
A deadly betrayal threatens to splinter Ragnar's army. Uhtred forms a cunning battle plan and finds an unexpected ally in young Edward.
A message from Uhtred and the machinations of Skade exploit divisions among the Danes. His health failing, Alfred wrestles with Æthelwold's fate.
Uhtred risks returning to Wessex to fulfill his vow to Brida. As the royal wedding approaches, Æthelwold spreads discord from the shadows.
At the end of his days, Alfred takes Uhtred into his confidence about his plans for Edward's uncertain future, but Ælswith charts a different course.
|Alexander Dreymon||Uhtred of Bebbanburg||10||✔||✔||✔||✔||✔||✔||✔||✔||✔||✔|
|David Dawson||King Alfred||10||✔||✔||✔||✔||✔||✔||✔||✔||✔||✔|
|Tobias Santelmann||Ragnar the Younger||4||✘||✔||✔||✔||✔||✘||✘||✘||✘||✘|
|Millie Brady||Princess Æthelflæd||9||✔||✘||✔||✔||✔||✔||✔||✔||✔||✔|
|Cavan Clerkin||Father Pyrlig||6||✘||✘||✘||✔||✔||✘||✔||✔||✔||✔|
|Eliza Butterworth||Queen Ælswith||10||✔||✔||✔||✔||✔||✔||✔||✔||✔||✔|
|Kevin Eldon||Bishop Erkenwald||8||✔||✔||✔||✔||✘||✘||✔||✔||✔||✔|
|Timothy Innes||King Edward||10||✔||✔||✔||✔||✔||✔||✔||✔||✔||✔|
|Jeppe Beck Laursen||Hæsten||9||✔||✔||✔||✔||✔||✔||✔||✘||✔||✔|
|Thea Sofie Loch Næss||Skade||8||✔||✔||✔||✔||✔||✔||✔||✔||✘||✘|
|Ola Rapace||Sigurd Bloodhair||7||✔||✔||✔||✔||✔||✔||✔||✘||✘||✘|
|Ian Hart||Father Beocca||10||✔||✔||✔||✔||✔||✔||✔||✔||✔||✔|
- Fight of Alton ("Episode 3.1")
- Battle of Fearnham ("Episode 3.1")
- Siege of Wincelcumb ("Episode 3.4")
- Battle of Beamfleot (893) ("Episode 3.5", "Episode 3.6")
- Battle of the Holme ("Episode 3.10")
- Skade and Hæsten's relationship; In the novel series, Skade encounters Hæsten and the two of them fall in love. Whilst in the television series, Skade appears to be completely disinterested in Hæsten and his advances.
- Æthelred commanding Aldhelm to sleep with Æthelflæd; Both in the novel and television series, Æthelred wants to divorce Æthelflæd. So he commands his right-hand man, Aldhelm, to sleep with her so she can be branded as an adulterer. In the novels, Aldhelm's attempts go unsuccessfully and when Æthelflæd is in danger from her husband, Uhtred comes to rescue her and ends up killing Aldhelm. Whilst in the television series, when Aldhelm is given the task, he already has been in admiration of Æthelflæd so he tells her of the plans her husband made. This results in Æthelred stabbing Aldhelm for disobedience, but he survives after being healed by Æthelflæd.
- Sigurd; The show has cut out the character of Sigurd who appeared in "Death of Kings" and "The Pagan Lord" of the novel series. The television series instead replaced/merged him with the character of Harald Bloodhair. Hence the name; Sigurd Bloodhair.
- Skade and Uhtred's relationship; In the novel series, Skade and Uhtred become lovers in "The Burning Land", after she convinces him that it was not her curse that has led to the death of Gisela. Whilst in the television series, Uhtred is reluctant to have her as his lover as she cursed him, and she was only trying to become his lover in order to manipulate him.
- Gisela and the last son; In both series, Gisela sadly dies when giving birth. In the television series, in "Episode 3.1", she died giving birth to her third son Osbert who lived. Whilst in the novel series, in "The Burning Land", it is said that she and the boy die. Which means that Uhtred and Gisela had four children together.
- Ragnar's death; In the television series, in "Episode 3.5", Ragnar is brutally murdered by Æthelwold. Whilst in the novel series, in "The Burning Land", Ragnar dies peacefully in his own home.
- Skade and Bloodhair's deaths; In the television series, Bloodhair is killed by Skade in "Episode 3.7", and Skade is later killed by Uhtred in "Episode 3.8". Whilst in the novel series, in "The Burning Land", it is Bloodhair who kills Skade after she kept abandoning him for others. Bloodhair asks Uhtred to kill him as he knew he wouldn't survive long anyway due to previous injuries.
- Exiled from Wessex; In the novel series, after being outlawed by Alfred, Uhtred and Skade become lovers and they sail to viking Frisia and kill her husband Skirnir. Whilst in the television series, in "Episode 3.2" Uhtred decided to go north with his men and Skade as his prisoner. They're headed to Dunholm, to Uhtred's foster brother, Ragnar.
- Skade's imprisonment; Skade and Bloodhair are lovers but are separated when shes taken hostage by Uhtred. Bloodhair tries to get Skade back by threatening Saxon prisoners outside the fort the characters are in. In the television series, in "Episode 3.1", his attempt is unsuccessful. Whilst in the novel series, in "The Burning Land", his attempt is successful. However, not long after she gets taken captive again.
- Uhtred's children's whereabouts after exile; In the television series, in "Episode 3.3", King Alfred, as revenge, tells Father Beocca to have the children brought into Winchester for religious instructions; to be baptised and raised as Christians. Whilst in the novel series, they are given to the Lady Æthelflæd, to live with her at her estate in Mercia.
- Father Pyrlig; In the novel series, in "The Burning Land", during the Battle of Beamfleot (893), the West Saxons manage to seize the first fort and try to assault the second fort but struggle to scale the walls. Father Pyrlig comes up with an amazing plan of throwing a bunch of live beehives onto the walls of the castle. This successfully distracted Hæsten's men and allowed the West Saxon fighters to capture the castle. Whilst in the television series, this did not happen. The whole battle took place outside the castle's walls.