Himself - Testifies Before HUAC (archive footage) (uncredited)
Jack Lemmon
Himself - Oscar Sequence (archive footage) (uncredited)
Walter Matthau
Himself - Oscar Sequence (archive footage) (uncredited)
Joseph McCarthy
Himself - Baits Reds (archive footage) (uncredited)
David Lee McLain
Keystone Fireman (uncredited)
Charles D. Miller
Party Guest at Douglas Fairbanks' Mansion (uncredited)
Annie Muñoz
Daughter of Movie Star (uncredited)
Pauline Olsen
Charlie's Secretary (uncredited)
Lance Patrick
Joe (uncredited)
Robert Peters
Great Dictator Cinematographer (uncredited)
David Robinson
Douglas Fairbanks' Manservant (uncredited)
Jessica Russell
Shirley (uncredited)
Reuven Russell
Waiter (uncredited)
Bob Sallese
Token Male Juror (uncredited)
Julius Schaub
Himself - Behind Hitler (archive footage) (uncredited)
Marc Ian Sklar
Parking Attendent (uncredited)
Mack Swain
Big Jim McKay
Daniel Taradash
Himself - Oscar Sequence (archive footage) (uncredited)
Philip Waley
Man at Train Station (uncredited)
Laurel Whitsett
Script Girl (uncredited)
Brad Yates
Paul (uncredited)
Did you know?
Trivia
While researching his role, Robert Downey Jr.' visited the Museum of the Moving Image in London and persuaded the staff to let him try on one of Chaplin's actual Little Tramp suits and boots. The latter fit him perfectly, and he found cigar stub in one of the pockets, which he subsequently treasured.
When Douglas Fairbanks swings down on the rope to meet Charlie, his foot is inside a loop at the end of the rope when he starts the swing in the wide shot, but when he lands in the tight shot, his foot is nowhere near the loop. Also the momentum created by the swing would have carried him much further than it actually did, i.e he wouldn't have stopped where Charlie was standing.
Charlie Chaplin: [after watching newsreel footage of Adolf Hitler to study Hitler's mannerisms and patterns of speech, in preparation for "The Great Dictator"]
I know you... you bastard!