Which author was an uncredited writer on the screenplay for Gone With Wind?

The uncredited writer on the screenplay for Gone With the Wind was Oliver H.P. Garrett.

While Margaret Mitchell wrote the original novel, and Sidney Howard received sole screenwriting credit, Garrett was a prolific screenwriter who contributed significantly to the film's script. He worked closely with director Victor Fleming, refining the dialogue and plot points.

Despite his major contributions, Garrett was not given credit due to a contractual dispute with David O. Selznick, the film's producer. He later received a substantial settlement for his work.