During WW1 cinema was used to share war footage and propaganda to those who went to watch and so more people went to the cinema to watch this.
After war less people went to the cinema but film production companies began creating films about the war by 1927 there was at least 15 war films based on WW1. Russian film directors and writers were intrigued by the war which is why majority of the soviet films were mainly based upon war but also was a movement for rejecting stylist concepts which were brought back in the form of film.