Public Nudity in the Middle Ages
Nudity in public was normal in the Midddle Ages. These pictures (downloaded from Quora) are from 14th century engravings and tapestries. After the Protestant Reformation nudity was considered sinful and was banned everywhere!
The fourth picture is an oil painting showing an idyllic scene.
It was posted on Quora in reply to the question "What is the most surprising thing about the Middle Ages?" (or something to that effect). Unfortunately I deleted the text after reading it, as I always do, so as not to clog up my inbox.
That last picture is clearly post-Medieval. I'd tag it as the "Romantic" style popular in the late 18th and early 19th centuries.
I might also note that there is a bit of prudery even in those four pictures. I see bare breasts but very few female crotches, and no penises or labial clefts. Note how those details are obscured by angles of sight and carefully placed hands.
As for whether the Reformation introduced a new hostility to nudity, I don't think it did. If It had done so, I would suspect that nudity would continue to be more prevalent in countries that remained firmly Roman Catholic, and I don't see any evidence of that.
It's certainly true that the introduction of Christianity to populations that formerly had no experience with it was a huge factor in creating that taboo. But in the Americas, this process was began in the 16th century by the Roman Catholic missionaries, who were not influenced in the least by the Reformation.
I thought the same as you until I read the Quora piece. Perhaps it was some sort of medieval artistic licence! I read some years ago that in rural and coastal England, nude bathing was common before the 20th century, but the males and females kept themselves apart when bathing.