The man who created the world's most valuable brand remains an elusive figure when not in his grotto, often shielded by the tinted windows of a personalised executive sleigh that serves as his mobile office. Friends say that money is not his motivation, even though he is apparently seeking now to sell off all or part of his privately held empire. Talking to the elves, seeing the children smile, guiding the creative side of Christmas, these are the things that drive him, he says.

Yet the owner of the trademark beard and belly-laugh is also a man shrewd enough to have grasped the money-making potential of Christmas when nobody saw it as a commercial enterprise at all, and many thought it doomed to merge with New Year. Santa Claus, a former bishop from Asia Minor, thought differently. He did not invent Christmas, he likes to say now, but he did re-invent it. Probably nobody has ever seen the link between reindeer and revenues more clearly. “Besides”, says one high-ranking elf, “he throws great parties.”

Santa's quirky management style, combining large quantities of mulled wine with a tight grip on the reins, has turned the ho-hum into the ho-ho-ho. Once just a two-day affair in churches and private houses, Christmas is now the biggest-spending item in most western countries after health care and defence. The logistics of that success require Santa to be in thousands of malls by day and down millions of chimneys by night. Advisers say he relies on a series of proprietary algorithms derived from Heisenberg's uncertainty principle, which allow him to be in an infinite number of places simultaneously so long as nobody believes he is really in any one of them.