If you go trawling through history for hangover cures, you'll come across some well-deservedly famous ones. The ancient Greeks, benignly enough, believed in eating boiled cabbage before meals to forestall drunkenness; Renaissance doctors believed in saffron's ability to combat alcohol's aftereffects; and some medieval Islamic authorities emphasized that calming mint concoctions could help out after a long night. Though these remedies might not strike us as especially effective-sounding, they also don't sound all that bad; even the medieval European tendency to chew on raw eel or soaked almonds after a bit of an overindulgent night doesn't look too bad (unless you have a violent aversion to sushi). Some other historical hangover remedies, however, got decidedly more unpleasant for those of a sensitive stomach.
The good thing about drunkenness is that it's consistent. People will reliably overindulge in every era of human existence, which means that cures will pop up over and over again. I'm deliberately excluding broader disgusting remedies that said they could cure everything from a sore post-drinking head to epilepsy, like Goddard's Drops (a 17th century cure allegedly made of ground up human skulls and dried vipers), because I only have so much space, alas. And, frankly, specific cures for hangovers are quite weird enough.
Ancient Rome: Prevent Drunkenness By Eating Some Swallow's Beaks
The Romans, like many other cultures, were less invested in the idea of helping the after-effects of drinking as they were in preventing the whole nasty hangover situation to begin with. They had various visually striking methods of achieving this, including the suggestion that drinkers should wear a garland of violets or particular shrubs, a thought that would please many Coachella attendees.
If that failed, though, it was recommended that the person rapidly consume either some wild boar or swine "lights" or offal (though it's unclear if they should be cooked first), or the beak of a swallow, after it was burned and ground down to ash. Bar snacks look extremely sensible by comparison.
Ancient Mesopotamia: A Soup Made Of Liquorice, Beans & Toxic Plants
This is renowned for being both one of the oldest hangover remedies on record and one of the most hideous soups I've ever heard about. The idea was to get the person who had over-indulged the night before, and force this concoction down his throat before he managed to indulge in any hanky-panky the next day:
The problem with this is that oleander is highly toxic, which may have worked in the hungover person's favor (it could induce vomiting) but could also kill them, which I think you'll agree is much worse than walking around all day with a headache.
Ancient China: A Little Nibble Of Horse Brain (Or Rocks)
Finding the original source on this one is very tricky, particularly because there's a risk of mistranslation: ma'nao, in Chinese, refers to both the brain of the horse and the mineral agate, and it can be a bit confusing to know which one it's referring to.
However, neither one seems particularly pleasant for a hangover cure, and ma'nao was definitely recommended as a way to beat the day-after blues in ancient China — though it's not entirely clear what one was meant to do with it, how to cook it, or how much you were meant to consume. Horses were expensive; a full brain may have been off the menu for everybody except the elites. One hopes they only suffered through a few small morsels.
1200s England: Washing One's Breasts Or Testicles In Vinegar
What on earth the thinking behind this one was remains a bit obscure; it might have to do with the idea of "cooling the blood," since medieval medical thinkers believed that some kinds of wine could heat up the body if consumed to excess, leading to illness. Whatever the reason, it's a pretty spectacular idea: according to John of Gaddesden, an English physician who wrote the medical treatise Rosa Medicinae and inspired Chaucer's doctor character in the Canterbury Tales:
Cabbages, you'll note, have trickled through from ancient Greek medicine, but where the salt on the testicles come from is entirely unclear.
1500s Russia: Rotten (& Anti-Semitic) Pork
This horrible practice apparently dates from the 1500s in Russia, a period in which anti-Jewish sentiment was growing in the country. It was meant to act less as a hangover cure than a permanent way to curb one's taste for alcohol, targeted towards habitual drunkards — with the side effect of harassing a Jewish person while you're at it.
Apparently, the idea was that somebody would take a piece of pork (consumption of which is, of course, not permitted for Jews who are keeping kosher), and hide it in the bed of a Jewish person for nine days. The extremely rotten pork would then be pulverized and fed to the drunkard, who would supposedly then "turn away from from drinking as a Jew would from pork." What a charming practice for everybody involved!
1600s England: A Barrel of Oysters, Some Anchovies & A Cow's Tongue
Samuel Pepys, the famous 1600s diarist, prepared this menu for a collection of head-aching guests on New Year's Day in 1661, presumably because he believed that these foods would help lessen their agony. He recommended a "barrel of oysters" (fresh or not is unclear), a big bowl of anchovies, a heap of wine and ale, and a particular addition: cow's tongue ("neat's tongue", as it was called at the time). The tongue would be smoked rather than cooked, if that makes you feel any better about the prospect of wolfing this spread down after a long New Year's Eve.
1900s America: Iced Clam Juice
Perhaps this will only gross out those among us who find the idea of clammy, salty water a bit disgusting, but "clam juice" — the run-off liquid collected when steaming clams and then cooled — definitely began to attain fame in the early 1900s in America as a hangover cure. Prominent clubs and hotels would apparently use an iced selection of it, plus an aspirin, as a potential breakfast item. It fell out of favour as things like Alka-Seltzer (and Dr. Pepper, which was originally marketed as a hangover remedy) came onto the market.
The interesting thing about this one, though, is that it's persisted: Gwyneth Paltrow recently recommended a dosage of clam juice as a hangover cure, and recipes abound for the foul substance to be mixed with everything from tomato juice to beer and downed as a cure-all the day after a wild night.
If nothing else, the lasting appeal of clam juice is proof (as with raw eggs and other modern horrible ideas for hangover remedies) that people really will try anything to dodge the prospect of having to make it through a workday hungover.