I don’t know about the supposedly “medieval” custom of ladies proposing to their fellows on Leap Days; it sounds like another example of what cultural historians call the invention of tradition to me. As stated again and again (especially on the internet), the “Ladies’ Privilege” dates from either the future St. Patrick’s dialogue with the future St. Bridget in the fifth century, or a Scottish Act of Parliament in the thirteenth century. In the Tudor-Stuart period that I study, I have found a few references to this odd day out, a day that doesn’t quite fit on the calendar, and one on which unusual things may occur, notably in the 1600 play The Maydes Metamorphosis, which contains the couplet Master be contented, this is leape year, Women wear breetches, petticoats are deare.
Actually there’s a long tradition of turning-the-tables in western culture: lords of misrule, charivari, the “world turned upside down”, festivals. Probably in other cultures too. So I think the irregularity of leap day became equated with a day when women wore the pants, obviously an equally unnatural occurrence. Not only do we have the Mayd’s Metamorphosis rhyme, but two images from several centuries later, both of which clearly express not-so-subtle political (King George IV wearing a dress) and social (bloomers!) sentiments.
The cartoons above are critical caricatures, but women acting like men could also be entertainment, as very literally illustrated by this 1896 poster for the Forepaugh & Sells Brothers Combined Circus (from the Library of Congress), featuring “”the leap year ladies of laughter” and “the only clown women who wear the comic crown”.
As far as I can tell, it is not until after the turn of the century, when we enter into a “golden age” for postcards, that we see the almost-exclusive association of Leap Year and the Ladies’ Privilege. Rather than “new women” pushing the boundaries, we see desperate women chasing men pictured on penny postcards. So many of these ephemeral items survived that they must have been manufactured by the ton, particularly in the leap years 1908 and 1912. After World War I, it was a different story. There are some lovely, wistful women, but also a lot of unattractive and old maids, doing anything to catch a man on that special leap day. Here is just a small selection of some random but (I think) representative samples, starting with some relatively mild examples from 1904 and then proceeding t0 the heady year of 1908 (popping ladies, man in a mousetrap).
And one postcard from 1912, another leap year that produced a mountain of cards portraying women in pursuit of men, and this one, which brings us back to who wears the pants.