Heh,
I'll sure know if I don't, because it will hurt like heck to wear a hoop skirt and several heavy skirts without it!
To expand on why wearing a corset is super important, even if you have a small waist already, let me explain further.
Probably the most important thing about accurately portraying a time period is the silhouette, or shape of the figure/shape of the dress. So many poorly done period dramas will slap a dress on a person without the correct undergarments, and it will look too loose or too tight in the wrong
places, baggy, wrinkly and so on.
This is the silhouette of the 1860s.
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What makes this different from the modern silhouette? The most important thing is that there is a
smooth, gently curved line from the waist to the bust. The bust also sits rather high up. (Another important thing with the 1860s silhouette is the dropped shoulder, meaning the shoulder seam is about an inch away from the actual shoulder, resulting in the appearance of broader shoulders. But that relates to the cut of the dress, not the corset.)
Compare that to the modern silhouette, which has a severe, abrupt line at the underbust.
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So, you think you could achieve the 1860s silhouette with modern undergarments? Absolutely not!!
Also, a few years ago, I made a little video on Instagram showing what one of my 1860s dresses looks like without a corset.
A tightly fitted bodice WILL look wrinkly and stupid if you are not wearing a corset. On the contrary, when you are wearing a corset, the bodice looks so fitted and smooth. I can tell immediately in period dramas if the actress is not wearing a corset because of the smoothness or wrinkliness of the bodice.
Lastly, for the purposes of evaluating a historical silhouette, please ignore the size of the waist in these fashion plates. Any figure, whether large or small, can have a historical silhouette with the right undergarments, because people of all shapes and sizes have existed throughout history. Having a small waist is not that important for an 1860s silhouette. What is important is the smooth, gently curved line from waist to bust, and the bust sitting up fairly high. Any woman can have that as long as they have a corset made to their measurements. Also, those fashion plates are exaggerated. Pretty much nobody had a waist that small. Kind of like how nobody has legs that long in the modern silhouette.
Also, regarding that 1860s fashion plate I edited with the black silhouette, here's the unedited version.
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