Today is the day we wear costumes that disguise our true identities, ring total strangers’ doorbells without fear, and eat more candy than should be allowed by law.

But why do we do this?  What does it all mean?

Our Halloween is actually the remnant of an ancient seasonal holiday celebrated by the Celts.  The Celts lived in what is now the UK, Ireland, and parts of northern France. Their year ended on November 1 and they celebrated the night before with a festival called “Samhain.”  On that day, they believed the gateway between our world and the spirit world was open.

Some say the tradition of costumes arose as a way to scare away these roving spirits.  Others say that roving spirits or fairies would go door-to-door during their night of freedom, asking for food.  If you gave food to the spirits or fairies, you got a reward.  If you didn’t, you got punished.  (You don’t want to be punished, in case you were wondering.)

But, you say, we’re not all Celts.  What’s the deal?

To make a long story short, the Roman Empire took over most of the areas where the Celts lived.  The Romans eventually became Christian, and many of the old pagan traditions were incorporated into Christian practice. In 835, Pope Gregory IV declared November 1 All Saints Day, also called All Hallows. This helped align pagan practices with Christian practices.  It put everyone on the same page, calendrically speaking if not philosophically speaking. The day before All Hallows Day was known as All Hallow’s Eve, or Halloween.

So there you have it!  When we celebrate Halloween, we’re actually acknowledging the complicated interplay between pagan and Christian, Celt and Roman.  And you thought it was just about wearing your pajamas to work.