Halloween has not always been about candy and costumes. Its history stretches back over 2,000 years, to the ancient Celtic festival of Samhain. The Celts, who lived in the area that is now Ireland and the United Kingdom, celebrated their new year on November 1. This day marked the end of summer, the harvest, and the start of the dark, cold winter, a time often associated with death. The Celts believed that on the night before their new year, the boundary between the worlds of the living and the dead blurred. On the night of October 31, they celebrated Samhain, when ghosts of the dead returned to earth. To ward off these spirits, the Celts lit bonfires and wore costumes. As centuries passed, the festival of Samhain merged with Christian traditions. In the 8th century, Pope Gregory III declared November 1 as All Saints' Day, a time to honor all saints and martyrs. The evening before, known as All Hallows' Eve and later Halloween, became a holy time of observance. When immigrants from these regions came to America, they brought their varied Halloween customs with them. Over time, Halloween evolved into a community-centered holiday, with activities like trick-or-treating, carving jack-o-lanterns, and costume parties becoming prevalent. Today, Halloween is a major folk holiday in the United States, combining different traditions from around the world.