Long before the introduction of postcodes helped get our Christmas cards delivered on time, the GPO Film Unit commissioned animator Lotte Reiniger to produce several short promotional films using her silhouette technique, aimed at giving the public a gentle nudge. ‘Christmas is Coming’ sees a grumpy Santa threatening strike action; the day is saved thanks to St. Peter’s calm assurances that this year us Brits will “post early for Christmas”. (Simon McCallum)