A propaganda film made during the Spanish Civil War in support of the Republican government against the rebellion by Gen. Francisco Franco's forces who were backed by Nazi Germany and Fascist Italy. The film would have been seen by those making it as a documentary.
| Writing | Prudencio de Pereda | Writer |
| Writing | John Dos Passos | Writer |
| Writing | Archibald Macleish | Writer |
| Writing | Ernest Hemingway | Writer |
| Directing | Joris Ivens | Director |
| Writing | Joris Ivens | Writer |
| Writing | Lillian Hellman | Writer |
| Crew | John Fernhout | Cinematography |
| Editing | Helen van Dongen | Editor |
| Sound | Virgil Thomson | Music |
| Sound | Marc Blitzstein | Music Arranger |
