The O'Leary brothers -- honest Jack and roguish Dion -- become powerful figures, and eventually rivals, in Chicago on the eve of its Great Fire.
| Writing | Sonya Levien | Screenplay |
| Directing | Henry King | Director |
| Writing | Niven Busch | Story |
| Writing | Lamar Trotti | Screenplay |
| Editing | Barbara McLean | Editor |
| Costume & Make-Up | Royer | Costume Design |
| Art | William S. Darling | Art Direction |
| Production | Darryl F. Zanuck | Producer |
| Art | Thomas Little | Set Decoration |
| Directing | Robert D. Webb | Assistant Director |
| Art | Rudolph Sternad | Art Direction |
| Camera | J. Peverell Marley | Director of Photography |
| Production | Kenneth Macgowan | Associate Producer |
| Production | Booth McCracken | Unit Manager |
| Sound | Eugene Grossman | Sound |
| Sound | Roger Heman Sr. | Sound |
| Sound | Louis Silvers | Music Director |
| Crew | Yakima Canutt | Stunts |
