As the noble/common distinction lost influence from the second half of the 18th century onward, it seems to have been replaced by a number of new distinctions, including moral/immoral, polite/impolite (polite society and the rest), and tasteful/tasteless. In general, the declining nobility portrayed the rising commoner, or bourgeoisie, as immoral, impolite (rude), and tasteless (crude). We can look at literature for evidence of this process.
As I’ve explored previously on this blog, Jane Austen‘s work offers a wealth of examples of the tasteful/tasteless distinction. In Chekhov‘s work, we see the moral/immoral distinction, and it’s not hard to find discussions of polite society and its opposite–impolite, crude, etc. There is also much talk of being cultured, well educated, refined, and their opposites. Boswell’s Life of Samuel Johnson is a good source for all of these distinctions.
The racial distinction between white and non-white (or Aryan/non-Aryan) also arose; however, this is a different kind of distinction because all of the others distinctions mentioned above served to differentiate between people of the same so-called race or nationality.
In premodern Europe, there wasn’t much talk of immorality; the more pressing issue was whether a person was saved or damned. You could break all kinds or moral norms but still confess and be saved from Hell. Or you could contribute money for the construction of a new cathedral and be rewarded with a crypt as well as a place in Heaven. The corruption of the medieval Church is a commonplace; however, the role of the Church was never to instill a sense of morality. It was just a way to bring some kind of order or structure to society.