Just last week we passed Twelfth Night, the twelfth day of Christmas, and now (for the Christians among us) we're in the season of Epiphany. We don't really do much to observe the Twelve Days of Christmas here in America, other than sing the song - 12 drummers drumming, 11 pipers piping, 10 lords a leaping, and so on. Twelfth Night (or What You Will) is a fairly entertaining Shakespeare play - its got cross dressing, role reversals, licensed disorder. Good times.
Through the Middle Ages, Twelfth Night featured ribald celebrations, presided over by a figure known as the Lord of Misrule (sometimes called the Abbot of Unreason, the Bishop of Fools, or later the Bean King). The Lord of Misrule is a very curious custom - a commoner or peasant is selected "King for a Day", and declares general merriment, calling for songs, entertainment, and mummery - to which everyone complies! Accounts of the practice speak of how gambling was done on the altars in churches, general public drunkenness and licentiousness were tolerated, or how the Lord of Misrule or Abbot of Unreason would mock the rich and powerful. Revolutionary stuff! (However, by Shakespeare's time, it seems the church put the kibosh on the Lord of Misrule).
The tradition of over turning the social order, and enacting a temporary king, goes back to the Roman festival of Saturnalia. During Saturnalia, masters would treat their slaves as equals, a slave would "rule" each household, and everyone would engage in quite a bit of revelry; the title Lord of Misrule comes from this Roman holiday. Saturnalia is for Saturn, who is associated with the Kronus of Greek myth; however, the Roman Saturn also presided over a deathless golden age, before he had to step down/was killed for the good of the world. Saturnalia celebrates the golden age of Saturn's rule. (Saturn and his wife had fertility associations, as well).
While the city folk might have practiced a 'toned-down' version of Saturnalia, out in the hinterlands, they did things the old fashioned way. They killed people. There are accounts from as late as the 3rd century, of Roman soldiers still electing Kings of the Saturnalia and actually murdering them at the end of the festival; one of the martyred saints, St Dasius, was executed for not taking his own role as King of the Saturnalia.
Ancient religions are littered with the practice of creating temporary kings - commoners or criminals given all the rights and privileges of kingship for a limited time - and then sacrificing them. (The Golden Bough features examples from all over the world.)
Strange to reflect how the medieval Lord of Misrule, mocking the social order, had it's roots in the 'king for a day' traditions of ancient Rome. Here in Philadelphia, there's this Mummers Parade every New Years - you want to see an example of the social order gone all topsy-turvy? Take a bunch of plumbers, cops and firemen, dress them in feathers and makeup and gay apparel, then have them march and dance and belt out jazzy show tunes. (And not suck at it). Yes, it's a mad, mad, world.
Using the Lord of Misrule in your game
For gaming, I like the idea of having a day when the social order is relaxed, and a new king, a Lord of Misrule, is elected to lead the festivities. (Spongebob and Patrick call it 'Opposite Day'). It's one of those quaint customs, with carnival overtones, that you could add to any large town or city to help bring it to life. Carnivals are great for mischief; big parties, balls, lots of folks walking around in masks; we'll revisit the theme.
Of course, when the adventurers head out to the frontier following a job offer, they encounter the Lord of Misrule again, when one or all of them are asked to preside over the local version of the festival after completion of some minor task. The characters are feasted, toasted, they have beautiful women thrown at them (or handsome men, for the ladies of the group), and then, as DM, you set up some kind of hideous death trap where the characters are meant to become victims of the cult - drugged wine at the big feast, or led into the woods (ala The Wicker Man) to the place of the sacrifice. Surprise!
See, it's drab to always be killing off your friends and neighbors for your pagan re-enactments; wouldn't it be much better to send word to the nearby town or city that there's some work for adventurers? Then you let the outsiders take on the role of 'king for a day' (or king for a week, or king for the festival, whatever) and sacrifice them, instead. Voila. The 70's The Wicker Man movie is an oldie but goodie.
Of course, since the characters are probably tougher than a bunch of zealous fertility cultists, they should be able to fight their way out once the trap is sprung. That's fine; the horror is all in the realization and set up.