Academy-award winning filmmaker Peter Jackson is best known for his big-budget fantasy trilogies based on J.R.R. Tolkien’s The Lord of the Rings and The Hobbit, which he made over the course of nearly 15 years. Now the New Zealand-based director is making his mark on a decidedly different genre with a documentary about World War I, They Shall Not Grow Old.
Using new technology to restore dozens of hours of footage captured a century ago on the Western Front, Jackson gives audiences an unusually human glimpse into life on the front line. After meeting with widespread critical acclaim when it premiered in Britain on the 100th anniversary of the war’s end on Nov. 11, 1918, They Shall Not Grow Old hits screens in select American cities on Dec. 17 and 27.
Jackson spoke to TIME about turning his obsession with WWI history into a movie, how the war inspired Tolkien and his thoughts on an upcoming Lord of the Rings adaptation for Amazon.
Your new film, They Shall Not Grow Old, uses technology to restore old footage from World War I. How is it different from other war documentaries?
I’ve seen documentaries that use the same footage we do from the archives of the Imperial War Museum in England. But because the footage is so damaged, you’re seeing the soldiers through the fog of time. They’ve always been these sort of Charlie Chaplin figures, grainy and scratchy. When I saw our film—colorized, stabilized, slowed down—it’s like blowing away that fog. These men filmed 100 years ago suddenly came alive.
You restored over 100 hours of film taken on the Western Front. What state was it in when you got it?
A lot of archive footage is third generation; it’s a dupe of a dupe of the original. So it’s grainy and the contrast is horrible. It has scratches or it’s shrunk in its tin cans, so the perforations are uneven—that’s why it jerks around on screen. Then there are splices where the film has been split in two. All those problems need a different fix.
How long did that take?
Well, first we had to work out what order we should do things—do you fix the scratches and then stabilize? Or do you stabilize first and then sort out the scratches? I had the museum send me a few minutes of footage and we spent about five months working out our pipeline. When we had finished with it, the quality exceeded my wildest dreams of how good it could look.
Is the film antiwar?
I didn’t have an agenda. I didn’t want to start thinking of ideas and then find out there was no footage to support them. The film doesn’t explore the causes of the war. The human experience, that’s the fascinating stuff that documentaries never really get into. They tend to be about the battles or the politics. When we did the audio, anytime someone mentions a date or a battle we’d cut it out. I didn’t want it to be anchored in a particular front or on a date. I wanted it to be a human experience. I was interested in the food they ate, how they slept, what they did on leave. It makes you think about what your life would be like if war broke out. Although I’m probably a little old to go to war now.
Why did you use audio from interviews with veterans to narrate the film, rather than a conventional script?
As soon as I saw the restored footage, I saw that what this film does is bring the humanity back to these men.
That’s when I had the thought that what the soundtracks should be is their voices telling us about their experience. I spent about a year and a half immersing myself in 600 hours of audio of interviews with veterans in the 1960s and 1970s.
Will you move away from narrative films in favor of documentary now?
I am looking at another idea that uses archives. I don’t necessarily prefer it, but my favorite part of making a movie is after everything is shot and you go into the cutting room with the editor. You’re not dealing with the weather and the set and 250 people. I never enjoy shooting a film because it never goes the way you want it to.
Within the 100 hours of picture and 600 hours of audio, there are probably eight or 10 films that should be made. Our movie is one tiny aspect of the war. But there are all sorts of stories: the Royal Flying Corps story. The women in Great Britain who had to go into factories for the first time. The nursing story. The colonial story—the troops from the Empire who were thrown into this war. Unfortunately, I wasn’t making those films, but they’re still there to be made.
How do you hope audiences will react?
What I hope this film does is make young people ask their parents or their grandparents, “Did we have anybody in our family in the war?” That’s a question I think a lot of young people don’t have any interest in asking anymore. If you’ve got an old grandfather, it’s possible that his father fought and that he’s heard the stories. In 20 years, when that generation passes, anything that was handed down to them by their parents will be lost unless they are asked questions.That’s how memory can be ongoing.
Is it true that you collect World War I planes?
Yes. I’ve been interested since I was a kid, because my father used to tell me stories about my grandfather’s service. I started with badges and scraps of uniform I’d buy at garage sales. As time went on, I got into guns, artillery and planes.
What do you do with all of it?
Gosh, that’s a tricky question. What do you do with a collection? Part of the fun is that there’s always something you haven’t found yet. The Germans had this flame-thrower they’d carry on their backs. I haven’t managed to find one yet.
J.R.R. Tolkien drew on his experience in World War I to write The Lord of the Rings. Having worked with both, do you see a link?
For me there are two areas where it’s blatantly obvious. First, there’s a scene in The Two Towers where Frodo and Sam are crossing the Dead Marshes, a series of pools with corpses visible under the surface. That certainly seems influenced by the Western Front. Second, as a British officer, Tolkien would have had a batman—a junior soldier who was sort of a servant. Samwise Gamgee is very much written as the batman to Frodo.
As a fan of the books, part of me would love to see an adaptation I’m not involved in. But I also feel a sort of parental connection to the material. I’m very happy to help if they want me.
Do you agree with fans who argue that most fantasy films are allegories for international politics?
I don’t think anyone’s watching Marvel movies to get a lesson about politics. But escapist films tend to be most popular in times of uncertainty. With the Depression, we got Frankenstein and Dracula. At the height of the Cold War, there were a lot of sci-fi and monster movies. In the 1970s, when the Vietnam War ended, you had a generation of filmmakers like [Martin] Scorsese and [Francis Ford] Coppola making more realistic dramas. When the fantasy films disappear for a while, we’ll know the world’s a safer place. May it happen as soon as possible.
This appears in the December 10, 2018 issue of TIME.