The Battle of Russia (1943) is the fifth film of Frank Capra's Why We Fight documentary series, and the longest film of the series, consisting of two parts. The film was made in collaboration with Russian-born Anatole Litvak as primary director under Capra's supervision. Litvak gave the film its "shape and orientation," and the film had seven writers with voice narration by Walter Huston. The score was done by Russian-born Hollywood composer, Dimitri Tiomkin, and drew heavily on Tchaikovsky along with traditional Russian folk songs and ballads.
Film historian Christopher Meir notes that the film's popularity "extended beyond the military audience for it was initially intended, and was the second in the series to be nominated for an Academy Award for Best Documentary Feature.
(Summary from Wikipedia)