They had all sorts of appliances for girls and women those times, that we would now consider torture devices.
Obviously corsets, even worn at night, and worn from a young age.
Also those hobble garters: straps limiting the stride, of which you can see and read more here
Posture collars, sometime separate, sometimes part of clothes: very high and stiff collars to keep the neck up straight, and often preventing turning the neck much and looking down.
Then there were backboards: a plank or bar along the back, belted at the waist and at the top with 2 shoulder straps. Those kept the shoulders backward and the chest sticking out more, and prevented slouching and such. (Such shoulder straps could also be part of the corset.) Apparently some were even equipped with a front attachment, either from the attached posture collar, or coming up from the waist belt, that forced the chin up. More details at Deportment Devices
I've also read of single gloves, or monogloves, where the girl's/woman's arms were put in a triangular sack at the back, strapped to the shoulders, and often tightened to bring the elbows close together, as a punishment device, but I have no idea if those were actually used, or just reports made up by fetishists.
Luckily times have changed, and those are almost exclusively used for fetish purposes nowadays; in comparison with some of those a modern chastity belt might not seem so bad 😉