Erich Wolfgang Korngold had written the scores for a number of important movies for Warners, including The Private Lives of Elizabeth and Essex. Korngold was told he was to write a score for a new picture, 'Kings Row'. According to Brendan Carroll in his biography of Korngold, the composer, thinking this was another royal story, set about writing the celebrated fanfare theme of the picture. Despite the wrong assumption, Korngold decided to keep and develop the theme into what has become a classic score.
Bette Davis showed interest in playing the Cassandra role. When she was turned down, she suggested Betty Field, who was eventually cast.
Ronald Reagan titled his 1965 autobiography after his biggest line in the film version of Kings Row: "Where's the rest of me?"
20th Century Fox attempted to buy the book's rights to turn it into a vehicle for Henry Fonda.
Among the actresses considered for the part of 'Cassandra', were Katharine Hepburn, Adele Longmire, Marsha Hunt, Laraine Day, Susan Peters, Joan Leslie, Gene Tierney and Priscilla Lane.
In the scene when Dr. Gordon and Col. Skeffington are first investigating the death of Cassie Tower and her father, the constable asks Dr. Gordon when coming out of the room where presumably Cassie was, if there were "anything else," to which Gordon replies, "Just something about the girl." Dr. Gordon then glowers at Drake McHugh from behind as Drake tells his made-up story (to protect Parris) about plans he (Drake) had with Cassie to run away. This is the only reference in the movie to Cassie's being pregnant, despite the fact that Dr. Gordon's assumption as to whom was the father is obviously what primarily led to the retribution later taken against Drake. Why the pregnancy was never mentioned is up for speculation: a part of the irony build into the script, or an issue with movie code of the time, or what.
The city depicted in the film is based on the actual Mid-Missouri town of Fulton, book writer Henry Bellamann's home.