A Lithuanian company plans to open a resort in the Maldives operated exclusively by blondes. Gierde Pukiene, the firm’s managing director, thinks the project could help counteract the dumb-blonde stereotype. “Our girls are very smart and they have degrees,” she said, according to the BBC. How long has the “dumb-blonde” meme been around?

Probably since the late 19th century. In 1868, a British burlesque troupe began performing a spoof of the Ixion myth at the Wood’s Museum theater in New York City. Featuring four blondes prancing around in tights, Ixion became an absolute sensation and outraged moralists who felt the girls were talentless wretches celebrated only for their bodies. The Ixion actresses were commonly referred to as the “British Blondes,” but at some point in the ensuing decade, the term “dizzy blonde” started cropping up: slang for the sort of risqué stage performer that the Brits had helped make popular, and more generally for “professional” beauties, with “dizzy” meaning foolish or stupid. Hence in 1889 the Kansas Times and Star noted, “Many of the local clergy last night warned the church members against a ‘Dizzy Blonde’ company coming to one of the theaters soon.”

The first dumb-blonde icon was probably the fictional character Lorelei Lee, the protagonist from Anita Loos’$2 1925 novel Gentlemen Prefer Blondes, later adapted into two films and a Broadway musical. A paid companion to wealthy, married men who thinks that “diamonds are a girl’s best friend,” Lorelei is perhaps more superficial than stupid, but she’s the sort of girl who gets ahead using her looks. Especially after Marilyn Monroe portrayed Lorelei in the 1953 feature film version, the idea that blondes are fun-loving and unserious became pervasive. In the 1960s, Clairol released the famous “Is it true blondes have more fun?” ad for its hair dye products, reinforcing the association. (In her book On Blondes, Joanna Pitman argues that the ur-dumb-blonde was actually the French courtesan Rosalie Duthé, who was satirized in the 1775 play Les Curiosités de la foire for her famous vacuity. Duthé was dumb and also blond, but it’s not clear to the Explainer that her contemporaries thought of her as a “dumb blonde,” per se.)

It’s possible to find traces of the dumb-blonde concept in the ancient world. Just like modern gentlemen, Romans valued blondness—they would dye their hair using goat’s fat mixed with beechwood ashes or vinegar concoctions or saffron. But as Pitman has noted, earnest types associated hair-dying with vanity and lack of gravitas. The poet Propertius, for example, wrote: “All beauty is best as nature made it … . In hell below may many an ill befall that girl who stupidly dyes her hair with a false color!” So while he didn’t connect blondness with idiocy exactly, he implied that women who wish to be blondes, and contrive to be blondes using artificial means, don’t have much going on.

As for why the dumb-blonde idea resonates—one idea is that it’s basically Propertius’ logic at work. It’s a fairly well-known fact that few adults are naturally blond, and that many apparent blondes actually dye their hair. If you dye your hair you must be superficial or vapid, Q.E.D. There’s also a theory, outlined in The Encyclopedia of Hair, that blondness connotes youth, since children are far more likely than adults to have naturally blond hair. Blondness, then, seems innocent but also naïve.

Academic studies show that blonde stereotypes go beyond joke level. For a 1999 study, researchers at the University of Coventry asked 60 men and 60 women to look at the same model wearing four different wigs—one platinum, one natural blond, one brown, and one red. Both men and women (but men more than women) rated the platinum blonde as less intelligent than the others, and described the natural blonde as “popular.” A German study conducted in 2004 showed that blondes completed lab tests more slowly after reading blonde jokes. (This is a well-known effect called the “stereotype threat.”)

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