Why bonkers Viking epic 'The Northman' just had to have 'a naked sword fight on a volcano'

Alexander Skarsg?rd spent a decade wanting to make the ultimate Viking movie, though initially, he didn’t imagine a world where he’d have to wear a flesh-colored thong during a naked duel to the death on top of an erupting volcano.

“There were definitely moments where I was crying and cursing myself and every one of us,” Skarsg?rd says of the climactic finale of director Robert Eggers’ 10th-century revenge fantasy “The Northman” (in theaters Friday), a story that's a reimagining of the Scandinavian legend that inspired Shakespeare's "Hamlet" but that's also “kind of in my DNA.”

The Swedish actor stars in the film as Amleth, a prince of an island kingdom forced to flee at age 10 when his beloved father King Aurvandil (Ethan Hawke) is murdered by his own brother Fj?lnir (Claes Bang). Twenty years later, Amleth lays waste to Slavic villages as a Viking berserker when reminded of his life’s mission – to avenge his father, save his mother (Nicole Kidman), kill his uncle – and enlists the help of young witch Olga (Anya Taylor-Joy) to infiltrate Fj?lnir’s farm in Iceland.

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Alexander Skarsgård plays a Viking berzerker out to avenge his father's murder in "The Northman."
Alexander Skarsga?rd plays a Viking berzerker out to avenge his father's murder in "The Northman."

And if the mere mention of Norse mythology and Vikings bring superhero Thor and a Minnesota football team to mind, think again. “Certainly since Wagner put horns on helmets in his operas in the 19th century, pop culture has been reinventing Vikings to be whatever they want to be,” says Eggers, who previously directed period films “The Witch” and “The Lighthouse.”

The aforementioned volcanic death match is just one of many crazy scenes in a film that Eggers took pains to make historically accurate. He and Skarsg?rd break down key aspects of “The Northman” that marry real Viking history and bonkers cinema:

Young Amleth (Oscar Novak) attends a feast hosted by his parents, King Aurvandil (Ethan Hawke) and Queen Gudrún (Nicole Kidman), in "The Northman."
Young Amleth (Oscar Novak) attends a feast hosted by his parents, King Aurvandil (Ethan Hawke) and Queen Gudru?n (Nicole Kidman), in "The Northman."

Prepare yourself for a Viking kid's very trippy initiation ceremony

Before he’s murdered, Aurvandil (Hawke) makes young Amleth (Oscar Novak) go through a ritual that readies the kid for the throne and is essentially a Viking bar mitzvah, albeit with more howling, farting and psychedelic drugs. In one of the stranger visions, Amleth views a “tree of life” bearing fruit that happens to be his ancestors. The scene was born primarily from Eggers’ exhaustive research: The design of the genealogical tree was “based on a tapestry from a Viking burial found in Norway,” he says, and the clothes and armor of the ancestors were inspired by archeological discoveries from before the Viking age.

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‘The Northman’ takes us out to a Viking ball game

Amleth partakes in a brutal, mud-bound round of Knattleikr, which Skarsg?rd describes as “a weird hybrid of lacrosse and MMA.” (The sport was so popular in Viking times that it was played year-round, even on ice “where they would use bones from animals as skates,” the actor says.) Adds Eggers: “A lot of historians think that they didn't even bother keeping track of the score. It was all about who's the last man standing.” Skarsg?rd put on muscular “heft” for the role but onscreen he had to go up against Icelandic strongman Haftór Bj?rnsson (aka The Mountain from “Game of Thrones”). “He's a really lovely guy but so big and so strong that in those scenes when we're running and he’d just lightly tap on my shoulder, I went flying.”

Björk plays the Seeress, a Slavic witch who reminds Amleth of his vengeful quest in "The Northman."
Bjo?rk plays the Seeress, a Slavic witch who reminds Amleth of his vengeful quest in "The Northman."

Bj?rk (yes, Bj?rk) plays a witch based on Ukrainian folklore

The Icelandic singer plays the Seeress, a blind Slavic witch who puts Amleth back on his vengeful campaign, and for her and Taylor-Joy’s Olga, Eggers pulled from Ukrainian and Transcarpathian folk beliefs and witchcraft techniques. While Norse mythology is a known commodity, “the Slavic religion in the 10th century is much more mysterious,” Eggers says. He also wanted something different than, say, what “The Vikings” TV show had done with “hordes and hordes of female warriors” that never existed. “It was interesting for me to explore these female characters who have agency and power, like in the patriarchal society, without rewriting history.”

Amleth (Alexander Skarsgård) befriends the enslaved Olga (Anya Taylor-Joy) in "The Northman."
Amleth (Alexander Skarsg?rd) befriends the enslaved Olga (Anya Taylor-Joy) in "The Northman."

A Valkyrie (with Norse grills!) rides on to warrior heaven

“The Northman” includes a couple of scenes of a helmeted woman riding a horse on a cosmic path to Valhalla, an afterlife for fallen Vikings. Eggers wanted his warrior heaven of sorts to look like “a spectral event that exists in nature but is also something sublime.” As for what appears to be braces in the “otherworldly” Valkyrie's mouth, he wasn’t inspired by ancient Scandinavian orthodontics. Viking skulls have been found to have “horizontal grooves in the teeth,” Eggers says. “The most popular theory currently is that this was just a cool adornment and they would fill that gap with pigmented enamel. We chose black, but there's a famous Viking king called Harald Bluetooth and there's speculation maybe he filled his gap with blue enamel.”

The naked volcanic climax incorporates real documentary footage

Because of “the macho stuff and the right-wing misappropriation of Viking culture,” Eggers was never into Vikings until he visited Iceland’s “powerful landscapes," he says. “I thought, if I'm going to do a Viking movie, it's got to end with a naked sword fight on a volcano." And it definitely lives up to being, as Skarsg?rd puts it, "just the most epic thing I'd ever seen." Fun fact: Documentary footage of a recent Icelandic eruption was used in creating the visual effects of massive flames and cinders – filming actually took place in freezing bad weather. “While Alex was shivering,” Eggers reports, “I was wearing the finest raingear that humanity has ever invented.”

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This article originally appeared on USA TODAY: 'The Northman': Alexander Skarsg?rd Viking epic is weirdly accurate