If a bra feels like a medieval torture device* to you, you are correct about one thing: They are, in fact, medieval (whether they are also torture really depends upon the fit).
[Image: Institute for Archaeologies, University of Innsbruck]
This bra has been dated from between 1390 and 1485 CE.
More accurately, it’s probably the remains of a “pair of bodies,” from which the modern term “bodice” originates. What we’re looking at is just shreds of the fabric that survived, which giving it the appearance of a modern bra.
The original garment probably looked more like this: