Comment by pphysch

Jill Fields at Cal State Fresno have actually narrowed it down to a (temporarily successful, but not in the long term, obviously) effort by the corset-making industry seeking to stay relevant after WWI during which corsets basically disappeared and there was an organized campaign that was organized both in person and through trade magazines. Women's silhouettes basically took a quick 180 right between 1900 and the start of the war only to turn very very retro in 1919 and while the first was organic and resembled how styles change in the century prior, albeit much quicker, the 1919 switch was openly plotted out in writing that was published but in such a niche publication that I get the sense that people not in the industry didn't even know that it existed. The cite to her paper on Google Scholar: https://scholar.google.com/scholar?cluster=17641417785638413...

You might have to shadow library this one, but it's a good read. Interestingly it seemed to be something entirely separate from Bernays whose observations were based on a derivation of what began as a homebrewed effort in a corner of the market. Valerie Steele wrote extensively about the trends and the after life but the source seems to originate in corsetry and ended up being copied by the garmet industry generally in the 20s.