History of Halloween

Halloween was originally a festival that the Celts celebrated called Samhain. They celebrated their new year on November 1. They believed that on the night before the new year was when the border between the land of the living and of the dead blurred the most.
They celebrated Samhain on the night of October 31, our Halloween, when it was believed that the ghosts of the dead returned to earth. In addition to causing trouble and damaging crops, Celts thought that the presence of the otherworldly spirits made it easier for the Druids, or Celtic priests, to make predictions about the future. For a people entirely dependent on the natural world, these prophecies were an important source of comfort during the long, dark winter. To commemorate the event, Druids built huge sacred bonfires, where the people gathered to burn crops and animals as sacrifices to the Celtic deities.
During the celebration, the Celts wore costumes, typically of animal heads and skins, and attempted to tell each other's future. When the celebration was over, they re-lit their hearth fires from the sacred bonfire to help protect them during the coming winter.