Samhain was a Druid holiday that marked summer’s end on October 31 and the coming of the cold weather, or season of the dead. The ancient Celts followed a lunar calendar, so the holiday began on the eve of October 31 and was marked by ritual burnings of crops and animals in bonfires as sacrifices to the Celtic deities. People cleaned out their homes that day to start the new year and new winter season fresh on November 1. Part of the tradition of Samhain was a cleansing of the old to make way for the new.
There was a belief that doors were opened between the Natural World and the Otherworld on Samhain when the dead could be set free from the Otherworld. People danced around the bonfires and wore costumes to honor the dead, to revere the deities, and to disguise themselves to hide from spirits they feared would be set free from the Otherworld. At the end of the celebration, people carried the bonfire home with them on tapers to light their hearths and keep the new fire burning the next year. It was considered bad luck if the fire went out.
The traditions of Samhain were modified by the Romans, who combined it with Feralia, the Roman day to celebrate the dead, and a holiday commemorating Pomona, the Roman goddess of fruit and trees whose symbol is the apple. As Christianity spread, the holiday was modified further as All Hallows Eve, the eve before All Hallows Day, or All Saints Day.