John Stringer and Dinah Starkey explore religious festivals and the science of illumination
As the year swings towards winter and the nights draw in, supermarket shelves fill up with pumpkins and hot dogs for Bonfire Night. Like our ancestors, we're responding to the age-old instinct to fight back the darkness with light. It's a reaction that cuts across time and cultures - enshrined in most of the world religions there is a "Festival of Light". In the cold northern regions it falls in autumn or mid-winter because that's the time when the sun needs our help. The Celts called this season Samhain, or Summer's End, and saw it as a time of death and new beginnings. Each year, the high king of Ireland took part in a ceremony in which he was ritually slain by wounding, burning and drowning and then be seen to come to life again to rule for another year.
According to Celtic belief, this was the time when ghosts walked abroad and the Lord of Death unleashed his demons on the world, so the Celts kept their house fires burning all night long on Samhain Eve (October 31) and kindled great bonfires (originally "bone fires") to strengthen the dying sun. The Christian church could not ignore this all-important festival. November 1 became All Saints Day, but the old Celtic belief survived in the tradition that spirits walk abroad on the eve of All Saints Day, or Hallowe'en. It was customary to set out gifts of soul cakes and wine for the visiting dead and from this tradition springs the modern custom of "trick or treating".
As for the bonfires, Parliament provided the perfect excuse when it set aside November 5 as a public holiday to commemorate the delivery of James I from the Gunpowder Plot. The timing guaranteed the festival an enduring popularity and - long after Samhain has been forgotten - children are still making effigies of luckless Guy Fawkes. Nobody knows when the custom of making Hallowe'en lanterns began, but sources show that country people were hollowing out mangel-wurzels (a type of beet) to make tallow lanterns as early as Elizabethan times. In Hinton St George, Somerset, they call them punkies and to this day the children of the village celebrate Punkie Night every November.