Meh, from the medrash brought earlier it's mashma that there was a concept of Kesuvah before the mabul, also from the story of Shchem.
I'm not saying that Yiddishkeit didn't add anything to the concept of a wedding, I'd have to be a fool to say that, but none of what Yiddishkeit (or any religion for that matter) added to marriage has nothing to do with the institution called civil marriage.