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Audrey Amidon, of the National Archives’ Motion Picture Preservation Lab, recently shared this film of German-American boys at a Nazi summer camp in Windham, New York, in the summer of 1937.

The German-American Bund, a pro-Nazi organization active in the second half of the 1930s, made the film to promote its summer camp experience. Amidon notes that the film stock reflects “excessive projection,” indicating that the movie had been shown many times, likely for recruitment purposes.

In Germany, the Hitler Youth and the League of German Girls expanded throughout the mid-1930s, becoming mandatory for children between 10 and 17 in 1936. Summer camp, hikes, and outdoor adventures were major components of the indoctrination practiced by these youth groups. Nazi ideology held that a vigorous outdoor life would bond children together and make them strong.

The approach would have been familiar enough to American parents, who had begun sending children to summer camps as a restorative and character-building measure starting in the early 20th century. Many of these camps were sponsored by religious or other interest groups, and featured a common slate of activities (the campfire, swimming lessons, arts and crafts) that could be leavened with songs and activities particular to the camp’s special interest.

The Bund camp followed this recipe, as the video shows, while adding a military touch to the proceedings. The children wear shorts with lightning bolts (the insignia of younger echelons of the Hitler Youth) and practice flag drill.

The Bund reached the height of its popularity in 1939, when a rally at Madison Square Garden, held on George Washington’s birthday, drew 20,000 people. The American government outlawed the organization in December 1941, after the United States entered World War II.