I found a couple of these in a dumping area from the 1930s-1950s period. One of them is pictured in the first group pic on my page here: https://www.glassbottlemarks.com/milk-glass-jars-vintage-cold-cream-salve-and-ointment-jars/
On the ones I have, the bottom is marked "MADE IN U.S.A.". I would assume this was once a very popular product, such as a beauty cream or ointment of some kind, sold in both the US and Canada, and probably other countries as well.
It would be neat to find one with a label still attached to know for sure!! No idea on maker, but Hazel-Atlas would be likely contender since they made gobs of milkglass jars.