Take the Roman festival of Saturnalia, the gift-giving Norse god Odin and the Pagan habit of bringing evergreen plants into the house at Midwinter.Add a benevolent fourth-century bishop, some drunken medieval singing and a nineteenth-century American poem.Sprinkle with the Christian tradition of Jesus being born on 25 December and stir well.Allow the mixture to absorb other influences over hundreds of years and serve with a plum pudding that may or may not have plums in it.Drawing on these multifarious ingredients and more, Caroline Taggart takes a fascinating and quirky look at why we celebrate Christmas the way we do.Illustrated in glorious full colour with images from the British Library Collections, this is a joyful journey through distant lands and ancient customs, finishing with a few thoughts on what our future traditions might be.