On Friday night, we marked a holiday that almost always manages to pass without comment. Every kid loves Halloween, but enthusiasm for the holiday among the young is no excuse for dismissing it as "childish" rather than examining it seriously. Halloween is seen as a fact of life, an amusing bench-mark in the celebratory vacancy that stretches from Columbus Day to Veterans Day. But history has some explaining to do when it comes to Halloween; its prominent place in the American calendar requires some justification. Indeed, it's a strange bird.

Halloween's peculiarity derives from its unique heritage. The holiday comes down to us from the remote past and should be understood as "twice-appropriated." The inhabitants of pre-Christian Britain and Ireland celebrated a festival on Oct. 31 in honor of Sambain, the god of the dead. This celebration also coincided with the beginning of the New Year (Nov. 1) in both Celtic and Anglo-Saxon observance. The festival was thought to represent a time of unparalleled interaction between the worlds of man and spirit; celebrants lit bonfires to ward off evil spirits and diviners claimed that the day marked an ideal moment to prognosticate concerning marriage prospects, luck and health.

Christianity appropriated the festival in the ninth century with the establishment of All Saints' Day. This liturgical observance was meant to honor the lives of Catholic saints and was held on Nov.1. The Church designated the preceding evening vigil as All Saints' Eve, but both holidays became known by their more vulgarized names: All Hallow's Day and All Hallos' Eve. In 998, the Abbot of Clugny instituted an accompanying celebration on Nov. 2, which became known as All Souls' Day. Thus, the Church used this two-day period to commemorate the entire deceased community of Christians, and both holidays remain in the Catholic calendar (the Church of England eliminated All Souls' Day during the Reformation, but reinstituted it in 1928).

In medieval times, a series of customs developed around "Hallow E'en" (Hallow Evening), many deriving at least in part from the holiday's earlier pagan incarnation. It became traditional to eat nuts and apples; the nuts were especially important because young girls were encouraged to watch them as they roasted, interpreting their behavior as an omen of the faithfulness or inconstancy of their beloveds--if the nut cracked or jumped, one was thought to be in trouble. The relationship between this custom and the Celtic belief in the power of New Year prophesies seems clear enough. Other traditions of note included "bobbing for apples."

But the Christian festival of All Hallows' Eve maintained its connection to deep spiritual anxiety. Also inherited from pagan times was the belief that the vigil represented a relaxation of the border separating the world of the spirit from the human sphere. All Hallows' became associated with witches, elves, fairies and all their manifestations (e.g. black cats); it was thought to be a time of unprecedented, frightening spiritual interference in mortal lives.

The holiday was appropriated a second time into secular American culture. Scottish and Irish immigrants brought the practices and observances of All Hallows' to the New World, and gradually it began to take on its rather innocent appearance. Today, of course, Halloween is a time for games, parties, trick-or-treating and watching horror movies (although rarely "scary" movies). Or is it? When we look at it closely, is there not something more to Halloween even today?

Even the small child notices that beneath all the fun spookiness of the day there lies something deeper (and perhaps darker). There must, after all, be a reason why the holiday has been so enthusiastically appropriated by secular, mainstream culture. Bobbing for apples is fun, but it's not that fun. Halloween has such staying power because secular America gets many of the same things out of the holiday that the Celts and Medieval Christians did so many years ago. Halloween the popular celebration is a comforting, attractive gloss on the subject matter that lies at its core. Even for us "moderns," Halloween remains a day for pondering the supernatural--it's just that we do it with a Simpsons episode or a masquerade rather than with a bonfire or a mass.

Halloween lets us off easy, but it should not be underestimated--it serves a real function. Not surprisingly, Edgar Allen Poe, the patron saint of Halloween, captured the spirit of this enigmatic holiday best in one of his early poems: "Thy soul shall find itself alone/'Mid dark thoughts of the gray tomb-stone." I hope you all had a good one.

Eric M. Nelson's column appears on alternate Mondays.