The JH seems to be some kind of a crack shot, the JC is into money, the JD is into booze, the JS, er, no idea. That could be a blackbird on his arm. He looks cross, anyway.
I have other packs from central Europe that depict jacks in various pursuits that people other than young men might frown on. It seems to be a tradition of some kind, but I can't look it up because I'm too busy right now marking these CE217 assignments (plus doing all the admin the universiy casually flings my way, plus speaking to journalists who contact me out of the blue, plus 150-minute Skype consultancy calls).
I'm going to have to stop bidding for cards on eBay for a while, anyway, as my wife has started with the "how many packs of playing cards do you want?" line and won't accept "all of them" as an answer. I'll have to lie low for a while.