Well, it all started back in Ireland...
And it started with a man named "Nasty Jack" (some title him "Stingy Jack"). Now, Nasty Jack was just that- a mean old man who stole, never gave to charity, and played tricks on everyone- even the Devil himself! How's that for a bold move? It happened as so... One night, Nasty Jack was walking out in the dark when he came on the Devil planning mischief. "Devil," Jack said, "how can I help a kindred soul?" because the only kind things he did for anybody always involved trouble for somebody.
Well, the Devil was right glad to see one of his own and said, "I'm fixin' to spoil all the eggs in yonder henhouse, and cause the goodwife of the house some trouble- but I can't get past the watch dog to do it!"
"Devil," says Jack, "here's what you do... You see that tall apple tree, the one that droops over the fence? Go climb up and out on that limb there, and you'll be right on top the henhouse in no time!" Well, the Devil thought that was grand, and followed Jack's advice. When the Devil was in the tree, Jack pulled out seven silver crosses and laid them round the trunk, and trapped him! Now, the Devil didn't like being cornered, much less being tricked by a mortal, and cursed a blue streak.
Jack was a-laughin' and dancin' round the tree with joy at having outsmarted the Devil, so he didn't mind what was going on overhead. (Besides, he'd said worse things himself!) When the Devil realized that laying down curses on Jack's head wasn't going to work, he set his mind to bargain. "Jack, what do you want to let me down from here?" he asked.
"Just a trifle.... I know I ain't the best of men, but I don't want you takin' my soul when I die. Swear I'll be safe from Hell, and I'll let you down!" Of course, the Devil had no choice but to agree. A long time passed, and Jack grew nastier than ever 'til he died. His spirit went to the pearly gates, but St. Peter turned him back because there was no room for an unrepentant sinner in paradise. Well, the next natural place to go for Jack was Hell- but the Devil kept his promise not to take Jack's soul and turned him out.
Jack had nowhere to go, and couldn't find his way in the dark, so he stole an ember from the fires of Hell to light his way. However, the ember was too hot for him to carry, even as a ghost. So Jack took a turnip he'd stolen while he was living from his pocket, and used his trusty pocketknife to carve it into a lantern. He then put the hellfire into it and it lit his way back to the mortal world.
However, once he crossed to our world, he found he couldn't do any of the trouble-makin' things he used to enjoy... He couldn't steal, couldn't cuss at anyone so they'd hear him, and couldn't play tricks anymore. People couldn't even see him except at night! He was a doomed soul, forced to wander and wend his way in the dark for all eternity, with only a carved turnip for company. Those who knew him in life and saw his spirit took to calling him Jack of the Lantern, or Jack-O-Lantern... and that's where we get the name!