Margaret Dumont Biography
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Trivia

Last appearance of any kind was on the TV show
The Hollywood Palace in 1965, reprising her role as
Groucho Marx's straight woman. She died just days later.

She was bald and wore wigs for several years on and off camera.

Her screen persona was that of a stolid, wealthy society matron, which is exactly what she was: her husband, John Moller, was a millionaire industrialist, and she often commuted to filming locations from her mansions in Palm Springs, California, and Paris, France.

Started on stage in 1907

She was the god-daughter of author
Joel Chandler Harris.

Biography in: "Who's Who in Comedy" by Ronald L. Smith. Pg. 143-144. New York: Facts on File, 1992. ISBN 0816023387
Groucho Marx called her "practically the fifth Marx Brother".

Offstage, she usually called
Groucho Marx "Julie", which is short for Julius, Groucho's given name.

Some have argued that her image of the refined lady who did not understand the Marx Brothers' humor was an artificial one since she had a long career being a comedic foil in comedy stage productions years before her more famous work.
Source provided by imdb (Copyright) - The Internet Movie Database.