William Dieterle had a habit of directing with white gloves on. Robert Wise said that everyone thought it was because he had a germ or dirt phobia. During shooting of one scene, Dieterle noticed there wasn't enough mud on a carriage wheel. He pulled off his gloves, grabbed some mud, rubbed it onto the wheel, then wiped his hands on his pants and put the gloves back on to continue directing.
Judge John Hathorne was one of the judges at the Salem Witch Trials in 1692. He was also the only one who never apologized to the victim's families. His descendant, Nathaniel Hawthorne, changed the spelling of his surname in order to appear not so closely related to such an infamous ancestor.
In later years, Bernard Herrmann told how he created the strange, almost subliminal sound heard during Scratch's first entrance in the barn. He said he sent a crew to San Francisco at 4:00 in the morning to record the hum of phone lines. He combined these with the overtones of the musical note C painted directly onto the soundtrack, which, when run through a projector, created a sustained phantom tone, a "fundamental".
Thomas Mitchell originally was cast as Daniel Webster. While filming a carriage ride scene with young Lindy Wade, Mitchell lost control of the horses and was thrown from the carriage. He suffered a fractured skull and was in the hospital for 17 weeks but made a full recovery. Director William Dieterle re-cast Edward Arnold in the role with one day's notice. All of Mitchell's scenes as Daniel Webster then had to be re-shot with Arnold.
Walter Huston gave Scratch a folksy but sinister quality. In the original story, the character was much darker and more soft-spoken.