Stingy Jack was not a nice man, but he was a clever fellow. Twice he tricked the devil, and won a concession from the devil that he would not take his soul when he died. God would not allow such an unsavory character into heaven, and the devil could not have him, so Jack's soul was left to wonder on earth. The devil sent him off with one coal to light his way, and Jack put this into a carved out turnip. He was called Jack of the Lantern, and then Jack o' Lantern. In Ireland and Scotland people began making their own lanterns, hallowing out turnips and potatoes and carving faces. These the put in their windows to keep Jack and other evil spirits away. When people immigrated to the United States, they found the pumpkin, and American fruit, perfectly suited for their Jack o' Lanterns. In America we have our own Jack characters. The Disney version of Washington Irving's "The Legend of Sleepy Hollow" has the headless horseman throw his Jack o'lantern head at Ichabod Crane. In the Oz series we have Jack Pumpkinhead who replaces his head with a fresh pumpkin whenever his seeds start to spoil. He maintains a pumpkin field for this task. More recently we have Jack Skellington of Tim Burton's "The Nightmare Before Christmas."
most taken from history website http://www.history.com/topics/jack-olantern-history