D.W. Griffith filmed some battle scenes during actual battles at the front in France. While he was out near the front trenches scouting locations, his party came under a surprise German artillery barrage. Griffith and his assistant jumped in a nearby ditch, and when the barrage was over they emerged from the ditch to discover that although they were uninjured, a shell had exploded near the ditch, killing the two soldiers acting as their escorts, along with a dozen other soldiers standing nearby.
The movie was commissioned by Great Britain, which hoped that a depiction of WWI would help spur the United States to join the allies. Although D.W. Griffith had the cooperation of the British, French and Belgian governments to film in their territories, his cameraman, G.W. Bitzer, was of German descent and was not allowed in France. Griffith used an army cameraman instead.
The Pennsylvania Board of Censors demanded that D.W. Griffith cut scenes of brutality from the film. Griffith's response to those demands was to cancel the Philadelphia opening.
French battle scenes were staged in Surrey, England.
Cast member Robert Harron's entire family was cast in this film.
A bulk of footage was shot on the set from Intolerance: Love's Struggle Throughout the Ages (1916), which were still standing. Not only were free-standing sets built within the Babylonian Palace set, but dressing rooms and holding areas were set up underneath the massive staircase and in other covered areas. This was done because the Fine Arts Studio's facilities were already completely booked. According to Karl Brown, the crew on this film were better off than the other productions because they had a lot more space.
D.W. Griffith met Queen Mary on a trip to England while working on film, and later described it as the proudest moment of his life.
Griffith bought footage of the German army off of an Austrian-American officer, Kleinschmit, who had been arrested in the United States for espionage, and incorporated the footage into this film.