Growing up in America, Christmases in our house were always very “lively”, says Bill Bryson in his new audiobook The Secret History of Christmas. This was because whenever my father put up the Christmas tree lights, “there would be a terrific bang, a searing flash of light”, and he would be thrown “backward, at speed, on a more or less horizontal trajectory”. This, of course, was back when the lights had “bulbs the size of acorns” and the wires “positively crackled with energy”. Sometimes, if we were lucky, his body would “light up like a medical X-ray”. After all that, Christmas Day was “something of an anticlimax”. Americans don’t take it that seriously anyway – we’re generally still full from Thanksgiving. Plus, where I lived there was “always about six feet of snow outside”, so if you got a bicycle or roller skates all you could do was “ride around in tiny circles in the living room”.