The word Jack O Lantern was 1st used to describe a mysterious light seen at night flickering over marshes. When approached, it advances, always out of reach. The phenomenon is also known as will o the wisp and ignis fatuus (foolish fire).
In pop legend it is considered ominous and is often thought to be the soul of one who has been rejected by hell carrying its own hell coal on its wanderings.
In Ireland, where Halloween began, the first jack-o’-lanterns weren’t made of pumpkins. They were made out of rutabagas, potatoes, turnips, or even beets! There is an old Irish legend about a man named Stingy Jack who was too mean to get into heaven and had played too many tricks on the devil to go to hell. When he died, he had to walk the earth, carrying a lantern made out of a turnip with a burning coal inside. Stingy Jack became known as “Jack of the Lantern,” or “Jack-o’-Lantern.”
From this legend came the Irish tradition of placing jack-o’-lanterns made of turnips and other vegetables in windows or by doors on Halloween. The jack-o’-lanterns are meant to scare away Stingy Jack and all the other spirits that are said to walk the earth on that night. It wasn’t until the tradition was brought to the United States by immigrants that pumpkins were used for jack-o’-lanterns.