Halloween as we know it didn’t start out as costumes and treats. Actually the earliest celebrations were celebrations originated with the festival of Samhain, an ancient Celtic festival.
People would light fires and wear costumes to keep spirits and ghosts away and usher in the darker part of the year along with the harvest. The festival took place on October 31st through November 1st.
Later, November 1st was designated as All Saints Day. Pope Gregory III changed the Catholic feast of All Martyrs Day to November 1st and expanded the day to include all saints as well as Martyrs.
Into the 9th century, the Celtics were accepting of Christian beliefs and Samhain was replaced with a more church sanctioned day, All Souls’ Day, honoring the dead. Like Samhain, the day was celebrated with fires, costumes and parades. Some dressing as devils or angels. Some refer to All Saints Day as All-Hallows Eve, then later, Halloween.
Halloween in the United States was not popular til the 19th century. In the Southern colonies, there were some various traditions, such ghost stories or mischief, but it wasn’t until the mid 19th century, when the US allowed many new immigrants, particularly the Irish, that Halloween became popular. The blending of different cultures and beliefs have shaped Halloween to the festive day it is now.
As Halloween has evolved over the years, it has included, Autumn gatherings, pumpkin carving, costumes and some believe the barrier between the living and the dead is the thinnest, allowing for magic or witchcraft.