True Blood 's Eric Northman vs. The Northman : Alexander Skarsgård says similarities aren't a total coincidence

Even before we knew anything about The Northman, the latest movie from indie auteur Robert Eggers (The Witch, The Lighthouse), it already sounded like a True Blood spin-off for Eric Northman.

Alexander Skarsgård stars in the film as a Viking prince out for revenge against the man who destroyed his family — much like his True Blood character before he became a vamper. Skarsgård is well aware of these similarities, confirming, "It's not a complete coincidence."

"This is a straight-up sequel," he tells EW in jest. But he does give props to the HBO hit show for setting him on the path to creating The Northman. "I want to credit True Blood a little bit, at least for giving me that idea," Skarsgård says.

"I was kind of harboring this idea, this dream of one day making an epic Viking movie, but in a truly authentic way, that would capture the essence of the old Icelandic sagas and the poetry — that stark, laconic, harsh world and characters and tone," the actor explains. "But it was a distant dream 10 years ago."

Then, in True Blood season 3, Skarsgård's character got an origin story. We learned that before his vampire transformation, Eric Northman was the son of a Viking king named Ulfrik Northman. In flashbacks, Eric witnessed a pack of werewolves commanded by the vampire Russell Edgington kill his family.

Aiden Monaghan /Focus Features; HBO Alexander Skarsgård is well aware of the similarities between his new film 'The Northman' and his 'True Blood' character, Eric Northman.

"Malibu Canyon [in California] doubled for Sweden, but they were a couple of amazing days," Skarsgård recalls of shooting the flashback scenes. "I loved it so much. There was something coming out where I was starting to feel like, 'How amazing would it be to tell a Viking story on a bigger canvas, on a more epic scale — not just [with] a two-day flashback but actually have a whole Viking journey?'"

Skarsgård tried for years to make what would eventually become The Northman to no avail, until he met up with Eggers and the pieces finally started falling into place.

The film stars Skarsgård as Amleth in a story partly based on the Norse tale that inspired William Shakespeare's Hamlet and partly based on Viking legends. After witnessing the death of his father (Ethan Hawke) at the hands of his uncle (Claes Bang), Amleth flees his homeland only to return years later as a full-grown Viking berserker warrior seeking vengeance.

The Northman opens in theaters April 22.

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