Out of the dark ages

The runaway success of “Game of Thrones” has sent executives at the History Channel running to their books in search of the next medieval saga. Having had their own amazing success story with the bloody “Hatfields & McCoys” last summer, they know audiences have an unquenchable thirst for blood-and-guts revenge stories based in fact. They couldn’t have picked a better topic than the Vikings, who, unlike the characters in the “Thrones” novels by George R.R. Martin, were real, with real accomplishments, settling in many lands far from home. But boy, what they did to get there.

The series, which debuts tonight after “The Bible,” opens with a gory battle scene in 793 A.D. A strapping blue-eyed Norseman named Ragnar Lothbrok — there’s a mouthful — is running various sharp instruments through the bodies of his enemies in the gorgeous Irish countryside (yes, Ireland substituted for Norway, in most cases). There’s a lot of grunting and limbs separating from their owners and soaring through the air. Fighting alongside his older brother, Rollo (Clive Standen), Ragnar sees a flock of birds rise above the field of dead men and he gazes after them, wondering where they’re headed.

“Vikings” is a story of a people but also a story about wanderlust (and other kinds of lust). Its creator is Michael Hirst, who was one of the first writers who helped Showtime reach its present status as a cool cable station when he gave them “The Tudors,” the sexiest version of Henry VIII’s life story to date. Hirst spent six months researching the Norsemen. Even though they didn’t write anything down and Christian monks destroyed most of their culture, he was able to piece together enough of a story to launch a series that is meant to continue beyond one season.

“When the Vikings exploded out of Scandinavia at the end of the eighth century, they came out of nowhere,” Hirst told The Post on a visit to New York. “The Western powers had no idea about them. Within 40 years, they were in Paris. They colonized Iceland and Greenland. They were in Ireland. They set up a settlement hundreds of years [in North America] before Columbus. The Viking period lasted 400 years before they were Christianized.”

Fortunately, Hirst found enough material to base many of his characters on real people. His main man Ragnar was a real person, a farmer whose desire to see new lands went against the wishes of Earl Haraldson, a local chieftain (Gabriel Byrne).

“We know a reasonable amount about Ragnar. He was a great Viking leader. That comes out of myth and legend,” Hirst says. “We know that he sails to England. We know that he attacked Paris. We know that he had lots of sons, including Ivan the Boneless. And he was killed by being thrown into a pit of snakes by the Northumbrian king. His sons revenged him.”

Blue-eyed Australian actor Travis Fimmel plays Ragnar and Canadian actress Katheryn Winnick plays his wife, Lagertha, who fights alongside her husband in something called a shield wall, where the Vikings raise circular shields above their heads and move as one. The Vikings had surprisingly contemporary attitudes toward women — they could own land and divorce their husbands — and Winnick enjoyed Lagertha’s status as a shield maiden.

“She was a female warrior for the Dark Ages. Her role is to fight on the front lines, but also to call out commands and to plug up the holes in the wall when other warriors die with her own shield,” Winnick says. “Her mother was a shield maiden. I have a young daughter, Gita. And I am teaching her to do it.”

When Ragnar sets sail, his first stop is Lindisfarne, a small island off the coast of Northumberland in England. He and his men sack the monastery there, killing all the monks there except for Athelstan, the only one who can speak Old Norse. George Blagden, who plays the monk, says that he functions as the “eyes of the audience” when Ragnar takes him back to Scandinavia to use as his slave.

“Athelstan would be representing a Western society that modern-day viewers would be more accustomed to,” Blagden says. “He’s a Christian trying to deal with this completely alien, multideity society.”

Nine episodes of “The Vikings” will air starting tonight, and Hirst hopes to shed light on these people and the Dark Ages. “People will be surprised and astonished by what they learn,” he says. “The received idea about the Vikings is that they were really dreadful. They were always the ones that break down the door in the middle of the night and kill your beloved ones. And tear the crosses from your walls.

“I found in fact that they did have a culture. And in their social lives, the Vikings had totally different attitudes toward the women than the Saxons and the Franks. They were a much more democratic society.”

VIKINGS

Today, 10 p.m., History Channel