1935 German film
Tag der Freiheit: Unsere Wehrmacht (Day of Freedom: Our Armed Forces) is the third documentary directed by Leni Riefenstahl, following Der Sieg des Glaubens and Triumph des Willens. Her third film recounts the Seventh Party Rally of the Nazi Party, which occurred in Nuremberg in 1935, and focuses on the German army.
Tag der Freiheit was considered lost at the end of World War II, but an incomplete print of the film was discovered in the 1970s—the extant footage reveals Riefenstahl mainly reprising the approach she used in Triumph of the Will (1934), though certain more expressionistic sequences clearly presage the more audacious style she would adopt for Olympia (1938).
Plot summary adapted from Wikipedia, licensed under CC BY-SA 4.0.