Origins
Way before the Church arrived in Ireland and the United Kingdom, the Celts were the ones living there, 2,000 years ago. Their new year was on November 1, and they celebrated Samhain (“summer’s end”) the night before, on October 31. Samhain was a pagan festival, people danced around bonfires and wore costumes, crops were burned and animals sacrificed. Celtic people believed that on that night the dead were closer than ever to the world of the living, and ghosts, both evil and good, would join them for one night.
Costumes and Trick-or-Treat
Costumes were worn to avoid the bad spirits. If the ghosts mistook a person for one of their own, they would leave them alone. Another way to appease the dead was offering them some sweets.
Later influences
Roman festivals commemorating the passing of the dead and, later on, Christian influences, changed the festival of Samhain. The All Saints’ Day celebration had similar traditions and was held on November 1. Samhain and “All-hallows-eve» (can you already see the origin of the word Halloween?), an old name for All Saints’ Eve, gradually became the same thing.
Jack-o’-Lantern
According to Halloween – From Pagan Ritual to Party Night, on the night of October 31 “supplicants moved from door to door asking for food in return for a prayer for the dead” with “hollowed-out turnip lanterns, whose candle connoted a soul trapped in purgatory”. Pumpkins replaced turnips in the United States when the tradition reached the country.
Halloween as we know it today
Halloween arrived in North America and it changed a bit more there. Americans revived the old “trick-or-treat” tradition and started celebrating parties, telling ghost stories and mischief making, combining American costumes with the European ones. At the beginning it was a secular festival, but it slowly became a more community-centered holiday. But it wasn’t until the nineteenth century, thanks to the massive Irish immigration due to the Irish Potato Famine, when Halloween really started to be celebrated by everyone. The festival started to be aimed at the young to reduce vandalism in the 50’s and it led to what Halloween is today: a neighborhood holiday of kids in costumes asking for candy!