First off, I feel the need to emphasize how much this lifelong brunette detests the phrase "dumb blonde." It's a baseless stereotype generally leveled against women that often crescendos in sexist punchlines and idiotic assumptions about the correlation between the level of eumelanin in one's hair follicles and intelligence. And even though it might sound like I'm taking those terribly unfunny dumb blonde jokes far too seriously, scores of studies on the sociology and psychology of hair colors confirm that men and women alike tend to judge towheaded ladies as more incompetent and needier than their darker-haired galpals.
In wondering when and why such a random stereotype arose, I had figured it had plenty to do with Marilyn Monroe's 1953 performance in "Gentlemen Prefer Blondes" in which she plays the preferable blonde (which is kind of funny when you consider that Monroe, née Norma Jean Mortenson, was a brunette when she first headed out in Hollywood). It turns out, however, that the original dumb blonde -- the ODB, if you will -- came around a couple centuries prior.
French courtesan Rosalie Duthe is credited (or discredited) with starting the dumb blonde meme way back when in late 18th-century Paris. A trained ballet dancer and favorite escort of French royals and fashionable circles, fair-haired Duthe was not unlike a blonde Kim Kardashian of her day, famous for being beautiful, famous and slow-witted. In 1775, a one-act play was written involving Duthe that emphasized her trademark long, vacant pauses during conversations, and the dumb blonde joke went public.
A century later, the British had adopted the slang "dizzy blonde" to describe risque stage performers. In the 1920s in the United States, a dimwitted young woman was referred to as a "dumb Dora," who would soon evolve into the anonymous dumb blonde thanks to Anita Loos. In 1925, the popular Harper's Bazaar writer and screenwriter published the best-selling novel "Gentlemen Prefer Blondes" about a brainless blonde protagonist Lorelei Lee, whom Marilyn Monroe would play in the film adaptation.
And speaking of hair color stereotypes, two years later, Loos published a sequel: "But Gentlemen Marry Brunettes."
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