Prof. Warren
Secretary of the Navy
Tersh Jeterax
Mr. Stillwell
Dr. Henry L. Carlyle
Adrian Benedict
Dr. Wells
James McCullough / Ralph Graham
Major General Vanderlip
Dr. Bernard Fischer
Jonathan Wilson
Dr. Malcolm Couzzens
Sherman Wadsworth
Dr. Brooks
Anthony Vickers
Milo Bragg
Timothy Bryant
Arthur Evans
Roger Jameson
Ted Darby
Adam Stanton
Blacky Franchot
Napoleon Bonaparte (uncredited) (voice)
Mr. Fred Tiflin
Marchese Del Laudi
Father Massieu, Joan's Bailiff
Brig. Gen. Mel Gilbert
Mr. Wallace Sanford
Earl Huber aka Mathews
Lt. Aleksa Petrovic, Mihailovitch's Aide
Dr. Larry Forbes
Edgar Allan Poe
Henry Clay
Tod Fenwick
Dewey Roberts
Bob Mallory
Roger Chevis
Ed Shirley
Dr. Morton
Lieut. Jerry Banning
Dr. Joseph Goldberger
Narrator / Tom Thumb's Father (voice) (uncredited)
Dr. Gregory 'Greg' Lane
Dr. John 'Jock' McWade
Ned Morgan
Joaquin Murrieta
Dr. Semmelweis