Everyone in the 18th century went commando. During the Regency period and the 1820s, some people wore drawers and some people didn’t, and we’re frankly not that sure what the percentage breakdown was.
By the late 1830s, though, drawers were standard. The Workwoman’s Guide of 1838 states:
These are worn by men, women, and children of all classes, and almost all ages, under the different names of trowsers and drawers…Drawers for ladies and children are usually made of calico, twill, and cambric muslin. Those ladies who are invalids, or who ride much, frequently wear flannel or wash-leather drawers…For men, drawers are composed of very strong twill, calico, linen, flannel, and stockinet. (p. 53)
I drafted and sewed my own drawers following instructions offered by The Sewing Academy (slightly modified–see line C in the image above). Hopefully my pattern image will be useful to anyone following the same instructions. However, this isn’t a how-I-made-it entry. Mostly I’m just here to explain why split drawers exist and why you really should wear them under your historic costume.
Drawers expanded on the job done by chemises and shirts. They soaked up sweat, oils, and other bodily fluids, thus keeping petticoats and outer clothing clean and preventing their deterioration. As with chemises and shirts, people washed drawers often.
A standard pair of women’s drawers comprises a waistband with two separate legs attached. The legs overlap in the front and the back, but have a completely open crotch seam. Why, you might ask? Because removing them was next to impossible while wearing a corset and thickly layered petticoats. This allowed the wearer to go to the bathroom without taking them off. As a bonus, it kept them warmer while visiting the outhouse in January. Many costumers will add that they also make visiting a port-a-potty in a hoop skirt or corded petticoat far less traumatic than if one is wearing 21st century underwear or shorts, regardless of the season.