Biloxi Daily Herald, November 19, 1919. A vital sartorial tip: Never attempt to wear a barrel without suspenders. Unless you’re a showgirl working a gimmick to get a little press, at least. (Hey, does anybody know what a “picture hat” is?)
So here’s what I can tell you about the origins of the wearing-the-barrel trope qua signifier of destitution. Near as I can tell, it was born from the confluence of two prior memes. On the one hand, you’ve got the precedent of the “Drunkard’s Cloak,” which was a medieval and early-modern legal incentive against public inebriation. The association between habitual intoxication and poverty seems pretty clear, right?
The second precedent is the ascetic Greek philosopher Diogenes (circa 412-323 B.C.), who supposedly made his home in a big clay jar. “Jar” somehow got mistranslated as “barrel” in popular consciousness from the early-modern through the Victorian era. (And yes, there did used to be popular consciousness of Diogenes.) I’m guessing the guy-in-a-barrel has real early theatrical roots and takes off from there.