With They Shall Not Grow Old, director Peter Jackson has brought stunning realism to century-old footage of World War I.

At the beginning of director Peter Jackson’s World War I documentary, They Shall Not Grow Old, we see British soldiers preparing for battle as we’ve always seen them: flickering figures moving herky–jerky through a silent world of gray and black in old, faded newsreel snippets.

But then, at the moment the soldiers arrive on the Western Front, the veil of the past suddenly—startlingly—drops away, as Jackson’s high-tech restoration and enhancement of vintage motion-picture footage shifts to 3-D color. The cratered landscape, the squalor of the trenches, and the vast blue skies appear in brilliant hues, and the rumble and roar of the artillery is terrifyingly loud. The troops morph from vague shadows into smooth-faced teenagers with gap-toothed smiles who move about naturally. When their lips move, they speak in authentic British regional dialects.

Jackson’s 99-minute film depicts World War I as never seen before on the screen. It might be the biggest advance in the art of the war documentary since The Battle of the Somme, the 1916 British film that gave audiences their first extended glimpse at combat. (Jackson used some restored footage from the film in his movie.)

The project might seem like a departure for Jackson, a New Zealander best known for his Lord of the Rings and Hobbit trilogies. But Jackson—whose British grandfather, William Jackson, fought in the Somme offensive—has long been fascinated with World War I. Over the years he’s amassed a huge collection of weapons, uniforms, and other artifacts from the conflict, including vintage aircraft. (When Steven Spielberg made War Horse, his 2011 World War I epic, Jackson lent him three cargo containers of artifacts.)

“I grew up with my dad telling me stories [from the war] about his father—my grandfather,” Jackson explained in an interview with the BBC. “In a funny way, I am also a child of the First World War. My dad emigrated to New Zealand, where he met my mum, because his father had admired how the soldiers fought.”

And so when officials from Britain’s Imperial War Museums approached Jackson in 2013 and offered him 100 hours of footage from its massive film archive, it’s no surprise that he jumped at the opportunity to make a documentary about the war. The museum’s only requirement was that he use the material in a fresh and original way. Jackson wanted to see whether modern technology could make the century-old IWM footage look as if it had been shot with modern digital cameras.

“I wanted to reach through the fog of time,” Jackson told the BBC, “and pull these men into the modern world, so they can regain their humanity once more.”

World War I was the first war in history to be filmed on a large scale. Starting in 1915, the British military allowed filmmakers to venture into battle zones to make newsreels to boost public support for the war effort. One cameraman, Geoffrey Malins, who worked on The Battle of the Somme, made more than two dozen films of the war, and endured being wounded, gassed, and deafened by explosions to get close to the action. As film historian Luke McKernan has written, World War I cameramen also had to work with primitive cameras whose lenses couldn’t zoom in on action and slow film that made it difficult to shoot from a distance or in low light.

It would have been challenging enough for Jackson to render clear scenes from those murky originals, but the IWM digitized archival footage was also third generation—“a dupe of a dupe of the original,” as Jackson put it to a reporter for Time magazine—and badly damaged. The original film had deteriorated over time, shrinking so much that the perforations were uneven, making it run haltingly in a projector. In some spots, the film had split and been spliced back together. Even after the footage was digitized, the defects remained to be remedied.

In addition to the IWM footage, Jackson had another incredibly valuable resource at his disposal: 600 hours of interviews with World War I veterans and civilians filmed by the BBC in the 1960s for its landmark series The Great War. Jackson drew on the interviews to narrate his film, but much of the audio also had to be cleaned up and restored.

To see whether restoring and enhancing the archival film was feasible, Jackson gave digital scans of some of the footage to Park Road Post Production, a New Zealand–based facility responsible for some of the technological wizardry in his Lord of the Rings and Hobbit trilogies. Park Road, in turn, enlisted the help of Stereo D, a company based in Burbank, California, that had created 3-D versions of such Hollywood films such as Star Wars: The Last Jedi, Blade Runner 2049, and Terminator 2.

The IWM footage had been filmed with hand-cranked movie cameras, and the cameramen often couldn’t keep turning the crank at a constant speed. To get rid of the jerky movements typically seen in footage from that era, Jackson’s restoration specialists had to calculate the original cameraman’s filming speed and then sync it with the smooth 24-frames-per-second speed of modern movies. Once that was accomplished, however, new defects emerged, including gaps in the action that the erratic filming speeds caused.

To fix that, Stereo D’s artists had to recreate what the camera had missed. In one particularly striking scene, for example, a young soldier about to go into battle turns his head and for a moment gazes back at the camera with a world-weary wariness. In the original footage, “the shot of the soldier turning his head was missing five frames,” Mark Simone, a Stereo D producer, explained in an interview with MHQ. “There’s a lot of hand frame-by-frame paint work in the film. The skill of the artist comes into play. They’re having to imagine what it would look like in between, taking existing parts and manipulating areas to make it look real.” But in the end, he says, “you’d be hard pressed to notice the difference if someone didn’t tell you about it.”

Stereo D used other technological tricks to enhance the existing images. “Every shot is kind of unique, in terms of the treatment that it needed,” Simone says. “When you’re starting with not a lot of resolution, you don’t want to lose any of it.” In particular, they zeroed in on the soldiers’ faces, where, he says, “you can really see the humanity.”

The colorization process for They Shall Not Grow Old was especially complex. Jackson didn’t merely want to colorize the moving images; he insisted on making people, objects, and landscapes (down to the mud in the trenches) look exactly as they would have at the time. And so he traveled all over the Western Front, taking lots of color photographs from the precise locations where the cameramen had stood a century earlier. Jackson’s photographs provided vital information to Stereo D’s artists.

“Peter constantly said that there is this generic image that people have in their head of what World War I was like,” Simone says. “Gritty trench warfare. But a lot of the war was fought on farmland, in the summer. People were dying under blue skies.”

To help the artists render more-accurate colors, Jackson also gave them access to his massive collection of World War I artifacts, which they then could match with objects in the film. “We made several trips to New Zealand, where we could be surrounded by the uniforms and touch them and take photos,” Simone says. “With everything in the film, we had a true-life example to reference.”

The project’s massive scale forced Stereo D to devise some technological shortcuts. One big innovation was software that could assign different colors to thousands of different shapes and objects—and then adjust similar ones simultaneously. “If we wanted to adjust the look of the British uniforms, and make them a little less brown and more green, because that was the color of the dye,” Simone says, “we had a way to do that quickly, without starting from scratch.”

Brent Burge, a sound editor who has worked with Jackson on numerous projects, recalls getting a call from Jackson in 2015 to come look at the footage and discuss ideas for sound. “Originally, the project was going to run about 30 minutes,” Burge told MHQ. “But once Peter started working on the film, he turned it into what it needed to be.”

Burge and his colleagues worked on creating realistic sound to accompany the silent film footage. “We were using a lot of props,” Burge explains. “Peter has an arsenal that was at our disposal.” That enabled the technicians to record the sounds of World War I shells being put in cannons and the rustle of the very greatcoats and packs that soldiers wore to battle. To get the sounds of exploding artillery, the technicians went to a military firing range and put microphones next to the guns and at the blast sites.

Burge’s team also paid close attention to how the din of war was incorporated into the film, so that voices and sound effects would seem completely realistic. They even adjusted the volume of artillery blasts to account for distances to locations shown in the original film footage.

“In films, we’re often dealing with music,” Burge says. “But here there was no big musical flourish where the director said, ‘Lose the effects.’ ” It was about how the sound effects could create the realism of what it was like.”

One of Jackson’s most striking successes was recreating actual dialogue spoken by the soldiers in the silent-film footage. He relied on expert lip-readers to decipher what the men were saying and hired actors in the United Kingdom who were skilled enough to replicate the regional accents of the soldiers.

Jackson also deleted references to specific battles or dates from the archival interviews he used because he didn’t want to tell history in the conventional way. “It’s not the story of the war,” he explained to an interviewer for Variety. “It’s the story of the humans.”

In 1916, when movies were relatively new, The Battle of the Somme had a profound effect on audiences in Britain, the United States, and other countries by stripping away the romanticized view of war and showing them the brutality of combat at close range. “It is simply grim war, depicted exactly as it happened,” a newspaper reviewer wrote at the time. But that wasn’t completely true. At least one of the film’s most memorable scenes—a shot of British troops advancing at the start of the battle—most likely was staged far from the front lines.

And even when they shot authentic footage in trenches, the cameramen of the time couldn’t in fact depict the war “exactly as it happened,” constrained as they were by their primitive equipment and the limitations of the silent screen.

Instead, by relying on 21st-century filmmaking technology that scarcely could have been imagined in 1916, it is Jackson who has been able to show, for the first time, what those brave cameramen really saw.

They Shall Not Grow Old may well change the nature of war documentaries by inspiring other efforts to resurrect vintage film footage and transform it into similarly realistic recreations. Jackson has pointed out that the IWM has enough archival footage to make eight or 10 more films—ones that might focus on the Royal Flying Corps, military nurses, the colonial troops who fought in the war, or numerous other themes.

And plenty of other footage exists. In addition to the IWM collection, 25 European countries have digitized some 700 hours of World War I–era film. In the United States, the National Archives has digitized more than 200 World War I films and posted the collection on YouTube.

With They Shall Not Grow Old, Jackson has shown that it’s possible not just to restore those early moving images, but to glean new truths from them. 

Patrick J. Kiger is a journalist in the Washington, D.C., area who has written for GQ, the Los Angeles Times Magazine, Mother Jones, and other publications.

This article appears in the Spring 2019 issue (Vol. 31, No. 3) of MHQ—The Quarterly Journal of Military History with the headline: The Resurrectionist