Jack O'Lanterns are, of course, the icon of Halloween; creating them is a holiday tradition until itself.

They're also not a little eerie to look at, and many people might casually cite their association with Halloween as the reason why.

But the truth is, the jack o'lantern resembles something that we, as humans, are hardwired to be wary of.

The overly large and hollow eye sockets. The triangular hole where a nose should be. The very wide, stiff grin, which is not dissimilar to the rictus of a corpse...

Summarily, they look like skulls and dead faces.

Halloween was not the impetus for gourd carving.

It's been tradition for thousands of years, for varying uses, across cultures. But like so many Halloween-specific traditions, we owe the jack o'lanterns we know to the Irish and the Highland Scots.

But what we consider a jack o'lantern is actually version 2.0, or even 3.0. Because in the old world, there were no pumpkins.

The prototypical jack o'lanterns were actually turnips, or sometimes potatoes, that more or less looked like mummified Voldemort.

At first glance, they don't have a very fanciful origin story.

In Britain, as far back as the mid-1600s or so, any nightwatchman with a lantern was reportedly called Jack--"Jack" being the all-encompassing name that was given to a man whose name you didn't know.

You, dear reader, might notice that a great many trickster and wily sprites also have this name, such as Jack Frost and Jack and the Beanstalk, even Jack in the Box. They all invite mischief and surprise. But that's a tangent for another day.

Eventually, though, Jack the Nightwatchman, swinging his lantern in the distance, began to morph with a legend. Specifically, that of a particular motherf cker named Stingy Jack.

There are about a thousand variants, but the following two appear to be very popular.

Jack was a thief and a fiend. One day, while going about in all his nary-do-wellness, he came across the Devil himself. Instead of letting his soul be stolen, Jack tricked the Devil into climbing a tree.

And while the poor Devil was up there, Jack carved a cross into the trunk so he couldn't get down. When Jack finally took it easy on the Devil and let him out of the tree, he did so in exchange for the promise that the Devil would never, ever take his soul.

In the second version, Jack is still a thief and a fiend. By different means and in various settings, Jack tricks the Devil into morphing in a coin, and then he hops into Jack's wallet.

But to the Devil's disadvantage, there is also tiny blessed crucifix in the wallet, so the Devil is again unable to free himself.

Jack, again, extorts the Devil, promising his freedom only if he received the same promise from him.

The result of both stories is the same. Jack eventually dies, as one inevitably does.

But God isn't having any of his sinful thievery in Heaven, and the Devil swore that old oath never to take his soul.

But the Devil--being as kind as he is apparently gullible--takes up an ember from the fires of Hell, that will burn bright for all eternity. And he gifts it to Jack, so the poor fellow can see his way as he wanders the lightless countryside.

Forsaken by both Heaven and Hell, Jack hollows out a turnip to contain Hell's ember--a makeshift lantern, if you will. And so he, Jack o' the Lantern, was damned to wander the twilight realm of lost souls forevermore, with only a glowing turnip to light his way.

And faraway through the deep night, people could see the bobbing flicker of Jack's undying ember.

But were people actually witnessing a homeless ghost? Or were they seeing a march of the fairy folk?

Alternatively called ghost lights, hobby lanterns, or a will o' the wisp.

Scotland's Will o' the Wisp functions on the same premise as Stingy Jack.

Will, however, was a wicked blacksmith who botched the second chance St. Peter granted him at Heaven's gate, and likewise is so condemned to wander the earth forever with only a coal from the Devil to light his path. Will's "wisp" is a bundle lit to make a torch, whose moving, winking flame would, at a distance, also appear to be an atmospheric ghost.

Will o' the Wisp, however, would seem to be a little meaner than Stingy Jack. Jack may have thwarted the Devil, Will lures night travelers to watery deaths, as his light often appears hovering just above lochs.

These ghost lights and will o-the-wisps also have a scientific name: Ignis Fatuus, which in medieval Latin means "fool's fire."

Both Ireland and Scotland have no dearth of marshy terrain. These wetlands have a signature natural phenomenon: fire, spit up from the surface of the water, which occurs when gasses--specifically, those generated by organic decay--oxidate.

The result is phosphorescence: a flickering belch of flame.

Other proposed explanations include the bioluminescence of fireflies and particular forms of fungi, or the light reflecting off of whiteish-colored animals like owls, which would account for the more erratic and reactionary movement of the "flames."

These flames were explained by people via superstitions within the context of their cultures; id est, with fairy stories and ghost legends.

So what people were witnessing in the night honestly may have been fire. Just not fire carried by a restless soul who duped the Devil.

When the Irish and the Scots hit American shores in droves, so did the many elements that would eventually coalesce into American Halloween.

The first reference to a jack o'lantern in American writing is found in Nathaniel Hawthorne's "Twice-Told Tales" from 1837: "Why, it will gleam through the holes, and make thee look like a jack-o’ lantern!"

But the difference between the old world and the new was this: turnips were out, and pumpkins were SO in. Pumpkins are plentiful here, especially in the month of October--it's their harvest season after all. Plus, they were larger than turnips--about as big as a human head, really.

And that meant they were just big enough to look like haunted, disembodied heads, especially when they were carved with gruesome faces.

With such limitless possibilities for frights, Jack o'lanterns were favored for Halloween pranks. They were often stuck on the end of a pike, so rascals could go around terrorizing their neighbors. Boys would randomly prop a jack o'lantern up in front of darkened windows.

Imagine all the screams of fright echoing down the streets while glowing orange jack o'lanterns swung in the air and darted around corners.

Yeah, Hell Night and all those destructive pranks associated with Halloween are also considered to have Scotch-Irish origins.

You're welcome, America.