Before Halloween became commercialized, sold to adults to celebrate with sexy costume parties spiked with horror movies, long before Halloween became a lighthearted opportunity for children—their faces painted and ghostly sheets worn—to gorge on candies… even before it acquired its Christian overlay, Halloween was a pagan, probably Celtic, festival. The darkening days of autumn was thought to be a time of agitated spirits, when the souls of the dead wandered the earth on their way to the other side. Rituals were developed to protect humans from these spirits; they lit bonfires, and wore masks. Gifts of food and drink were left out to appease the wandering spirits—which might be the origin of today’s trick-or-treating.
Psychologically speaking, Halloween is all about death. With the days growing shorter and the nights longer, there is more to fear in the dark, including the ultimate darkness. Death is the hardest fact we know; inevitable, universal, and incomprehensible. Death challenges the meaning of every bit of our life, and/or provides it with meaning.
We in the West deal with the terrifying, enormous and mysterious fact of death… Not at all. Our defenses consist mostly of avoidance and denial. They are not very satisfying or enlightening defenses.