When Jack finally died, his soul went to Heaven. However, God refused to let him in because of his sins. Jack then went to Hell, seeking a place for his soul to rest. But the Devil, true to his word, refused Jack as well. Trapped between Heaven and Hell, Jack’s spirit was forced to wander around the world of the living with only a lantern carved from a gourd to light his way. Thus, whenever people saw the lights floating out of the bogs, they attributed them to Jack and his lantern as he wandered across the world seeking somewhere to rest.
The story of how the day of Halloween came to be associated with these ghostly lights and the story of Jack is harder to pin down. Halloween itself is a religious holiday which celebrates the lives of Christian saints, thus the original name, “Hallowed (holy) Eve.” But much of the way that Halloween is celebrated (including the carving of lanterns from gourds) can actually be traced back to the religious practices of the pre-Christian Irish and their festival celebrating the fall harvest, “Samhain.”
Originally, Samhain was one of the most important holidays in the Gaelic calendar. It was celebrated on October 31st, the beginning of winter, marking the death of the old year and the beginning of the process of rebirth in the next. And because winter is the time of year when vegetation dies, it also became a time to honor the spirits of people who had passed on. And this practice of honoring the spirits of the dead in the celebration of Samhain could be why carved jack-o’-lanterns became associated with Halloween.
It was believed that during Samhain the spirits of the dead would travel from house to house, seeking hospitality. To attract these good spirits, Irish households would carve lanterns from gourds and place them near their houses along with offerings to the spirits. And to frighten away evil spirits, they would carve ghoulish faces into these lamps. The traditions surrounding Samhain serve as models for many of the traditions surrounding Halloween, which implies that many of these pre-Christian practices managed to survive in some form to the present day.
As was often the case, the process of Christianization didn’t completely destroy these pagan customs. Instead, the traditions were kept largely intact and the stories surrounding them changed as their pre-Christian origins were forgotten.
It seems as though sometime after the 16th Century, the story of Jack and his lantern came to be associated with these traditional gourd lamps and people began to refer to them as “jack-o’-lanterns.” And as with many traditions surrounding Halloween, the Irish carried the tradition of carving jack-o’-lanterns with them as they immigrated to the United States.