Halloween or Samhain had its beginnings in an ancient, pre-Christian Celtic festival of the dead. The Celtic peoples, who were once found all over Europe, divided the year by four major holidays. According to their calendar, the year began on a day corresponding to November 1st on our present calendar. The date marked the beginning of winter. Since they were pastoral people, it was a time when cattle and sheep had to be moved to closer pastures and all livestock had to be secured for the winter months. Crops were harvested and stored. The date marked both an ending and a beginning in an eternal cycle.
The festival observed at this time was called Samhain (pronounced Sah-ween). It was the biggest and most significant holiday of the Celtic year. The Celts believed that at the time of Samhain, more so than any other time of the year, the ghosts of the dead were able to mingle with the living, because at Samhain the souls of those who had died during the year traveled into the otherworld. People gathered to sacrifice animals, fruits, and vegetables. They also lit bonfires in honor of the dead, to aid them on their journey, and to keep them away from the living. On that day all manner of beings were abroad: ghosts, fairies, and demons--all part of the dark and dread.
How Samhain Became Halloween
Samhain became the Halloween we are familiar with when Christian missionaries attempted to change the religious practices of the Celtic people. In the early centuries of the first millennium A.D., before missionaries such as St. Patrick and St. Columcille converted them to Christianity, the Celts practiced an elaborate religion through their priestly caste, the Druids, who were priests, poets, scientists and scholars all at once. As religious leaders, ritual specialists, and bearers of learning, the Druids were not unlike the very missionaries and monks who were to Christianize their people and brand them evil devil worshippers.
Pope Gregory the First
As a result of their efforts to wipe out "pagan" holidays, such as Samhain, the Christians succeeded in effecting major transformations in it. In 601 A.D. Pope Gregory the First issued a now famous edict to his missionaries concerning the native beliefs and customs of the peoples he hoped to convert. Rather than try to obliterate native peoples' customs and beliefs, the pope instructed his missionaries to use them: if a group of people worshipped a tree, rather than cut it down, he advised them to consecrate it to Christ and allow its continued worship.
In terms of spreading Christianity, this was a brilliant concept and it became a basic approach used in Catholic missionary work. Church holy days were purposely set to coincide with native holy days. Christmas, for instance, was assigned the arbitrary date of December 25th because it corresponded with the mid-winter celebration of many peoples. Likewise, St. John's Day was set on the summer solstice.
Good Vs Evil - Druids, Christains, and Samhain
Samhain, with its emphasis on the supernatural, was decidedly pagan. While missionaries identified their holy days with those observed by the Celts, they branded the earlier religion's supernatural deities as evil, and associated them with the devil. As representatives of the rival religion, Druids were considered evil worshippers of devilish or demonic gods and spirits. The Celtic underworld inevitably became identified with the Christian Hell.
The effects of this policy were to diminish but not totally eradicate the beliefs in the traditional gods. Celtic belief in supernatural creatures persisted, while the church made deliberate attempts to define them as being not merely dangerous, but malicious. Followers of the old religion went into hiding and were branded as witches.
Feast of All Saints
The Christian feast of All Saints was assigned to November 1st. The day honored every Christian saint, especially those that did not otherwise have a special day devoted to them. This feast day was meant to substitute for Samhain, to draw the devotion of the Celtic peoples, and, finally, to replace it forever. That did not happen, but the traditional Celtic deities diminished in status, becoming fairies or leprechauns of more recent traditions.