This undated (but apparently pre-1969) photo comes from a Flickr set of a Catholic wedding held at St. Francis Xavier Church in Kansas City Missouri (good pictures of the interior as it is today).
It’s an interesting piece of liturgical history. First, this convert, who frequently sits way up front, is amused by the typical Catholic pattern of almost everyone sitting way, way back, even at a wedding. The headwear of the women in the congregation is worth noting too. Many of the women wear hats and the veils worn are small, not like the ones we usually see today among Catholic veil-wearers.
Some other liturgical notes:
There are six candles lit, suggesting this is perhaps a simple Missa Cantata. Something I’ve never seen photos of before as far as I can remember. Interestingly, there are no chairs or stools for members of the wedding party, suggesting they stood or knelt for the whole Mass. At this wedding, the members of the wedding party are all seated in the sanctuary. It would be interesting to look at a bunch of old photos to see what the various practices were over time and in different locations.
As far as customs go, the photos show that the priest wore a surplice for the wedding itself with no cope.
The dress of the servers in white albs or cassocks with white surplices is interesting, one I don’t think I’ve ever seen before. This was (and is) as I understand it a Jesuit church (relevant because of, for instance, the Domincan parishes where servers were dressed as mini-Dominicans or mini-Dominican prelates.). Was this a Jesuit thing? Just an idiosyncratic local thing?