James Norton initially wanted to play William, Duke of Normandy, but due to contract restrictions from his role in HBO's The Nevers, he was only permitted to take on a character written to die, so he took the role of Harold instead.

Ingvar Sigurdsson took over the role of Fitzosbern from Joseph Mawle in July 2024, after Mawle had originally been cast in the part.

Filming took place in Iceland from March to July 2024, at locations including Heiðmörk and around Reykjavík, with the Battle of Hastings scenes shot on a farm at Hvalfjörður.

The exterior stockades of the Norman castle and the London scenes were filmed on sets specially built on the coast just outside Reykjavík.

James Norton was injured during production after falling from his horse on set.

The appearance of Halley's Comet in the closing episodes reflects historical fact and its famous depiction in the Bayeux Tapestry, and the series also incorporates the popular (though historically disputed) image of King Harold dying with an arrow in his eye, shown as an addition made to his corpse by William.

On Rotten Tomatoes the series holds a 58% approval rating based on 12 reviews, with critics praising the performances of James Norton and Nikolaj Coster-Waldau but criticizing the pacing and historical accuracy.

Historians noted numerous inaccuracies, including showing William and Harold both present at Edward the Confessor's 1043 coronation (they likely first met in 1065), Matilda of Flanders being wrongly portrayed as a torturer, and Edward the Confessor's mother being fictionally beaten to death rather than having her assets confiscated.

The show's racially diverse, colour-blind casting—such as Black actors Jason Forbes and Elander Moore playing fictional and historical English characters—drew criticism from some historians given that England was ethnically homogeneous in 1066.

A scene depicting Sweyn Godwinson exercising 'jus primae noctis' (the right of the first night) is based on a historical myth with no evidence it ever existed, similar to its fictional use in films like Braveheart.