Sheeran will play Sir Cormac, a highly ambitious - and deadly — protégé of a high-ranking church elder.
The 14th-century-set drama tells the story of a warrior knight in King Edward I's time who is broken by war but is forced to wield the "bloodies sword of all" after violence finds him again.
The role will mark Sheeran's reunion with creator Kurt Sutter. A fan of Sutter's bloody biker series Sons of Anarchy, Sheeran contributed a cover of Foy Vance's "Make It Rain" for the show's final season.
Might this lead to more Ed Sheeran on your television screen? The singer took part in NBC's live episode of Undateable and has a special, Ed Sheeran: Live at Wembley Stadium airing on NBC later this summer.
The Bastard Executioner, currently filming in Sheeran's native U.K., is set to air 10 episodes this fall.
Are you excited to see Ed Sheeran on the drama? Do you think he's got the acting chops?
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