True Blood's Alexander Skarsgård has spoken about his tough past in the Swedish navy.

The 36-year-old is best known for playing his vampire character, Eric Northman, in the hit tv show True Blood, and from his appearances in both blockbuster and indie films.

However, in his early twenties, the actor enrolled in the Swedish navy and commenced in rigorous training for fifteen months.

The actor told GQ Australia: "We were out in the woods in the middle of the winter for 10 days. We didn’t really have any food or any sleep. It got to a point where people started to hallucinate and, you know, talk to their weapons...And cry. There was a moment where you’re, like, ‘I’m gonna die in five minutes.'

"We were freezing cold and so tired and hungry. We came back to the barracks after 10 days and the captain said, ‘Now you’re gonna go out and run 20 miles with your backpacks.'"

The actor has brought his military training to several roles throughout his career, including the film The Last Drop and television mini-series Generation Kill.

Skarsgård has recently undergone a complete transformation, shedding weight for his role in the horror-thriller Hidden, which is due out next year.