After my last post about plus fours, someone suggested to me that women would not have worn knickers in the 1930s, and that their appearance in Cold Comfort Farm was due to Hollywood taking liberties, which we know they often do. So I decided to do some more research to see if I could find any evidence of actual '30s women wearing knickers, and did I ever! Most of the useful information and photos in this post come from this Sportswear Workshop written by the very knowledgeable FuzzyLizzie on the Vintage Fashion Guild forum. She also has many more pictures like these, among other interesting subjects, on her website.
It appears that women have been wearing short pants for activities such as hiking, camping, riding, sports, etc, since the late 1800s-early 1900s when they appeared as long bloomers:
It looks like they really caught on in the '20s, as I was able to find quite a few examples of women wearing them:
Some illustrations and patterns (if only I had this first one!):
And even some real-life examples:
I found fewer examples from the 1930s. It appears that as the 1930s progressed, and as shorts and slacks became more acceptable and popular, knickers for women were largely abandoned. Here is an ad from the early '30s showing both options, and another illustrating riding breeches:
I wonder if another factor could be the preference for more feminine fashions in the 1930s, compared to the more boyish styles of the 1920s. In any case, it appears that wearing knickers in the '30s was certainly acceptable, perhaps just not quite as fashionable. Since Cold Comfort Farm is set in the early '30s, and as that happens to be my favorite part of the decade as well, I will certainly feel no qualms wearing my plus fours camping, hiking, and even (miniature) golfing!