A ceramic figurine called a 'caganer' of Britain's Queen Elizabeth at the Santa Llucia Fair in Barcelona Lluis GENE/AFP/Getty Images

You think your nativity play is different? You ain’t seen nothing yet.

For at least the past two centuries, the traditional nativity scene in Catalonia — you know, the usual suspects of Mary, Joseph and the shepherds gathered around the baby Jesus in his manger — has been enhanced by a character called a caganer. There’s no delicate way of putting this so the most polite translation is “the defecator” as, despite an innocuous-looking appearance from the front, its buttocks are bare with each one containing a small, brown deposit beneath. Charmed, we’re sure.

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Reasons for his existence vary. The BBC has done some serious digging with one local in Barcelona explaining that, “It’s typical of Catalonia. Each house buys one for Christmas, I don’t know why (we do it), it’s just a tradition.” More specific still is Joan Lliteras, who can certainly call himself a caganer connoisseur. “There was the legend that if a countryside man did not put a caganer in the nativity scene, he would have a very bad year collecting vegetables,” he said, claiming that the figurine is a symbol of fertility and good fortune.

Lliteras has a not inconsiderable collection of some 600 caganers as well as being the founder of an association so he knows of what he speaks. “The caganer is never in the front of the nativity scene. That would be a lack of respect. He’s always hidden in a corner, under a bridge or behind a tree and every morning the children play a game, hunting for the caganer.”

It’s now turned into big business with the inevitable celebrity spin-off. Christmas markets sell the likes of politicians, soccer players, foreign presidents, rock stars and royalty. While Queen Elizabeth II is popular (when you her particular pose, you know why) her son Prince Charles is considerably less so (art imitating life? We couldn’t possibly comment). And naturally, it looks as if Prince William and Kate Middleton will be joining their family in time for the royal wedding.

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But what of President Obama? “I’m buying four Obamas to send back home,” American Tom Burns confirmed. “I’m buying Obama,” another shopper from San Francisco told the BBC. “With all due respect Obama, we love you dearly.” Indeed. But if there’s one word to be associated with the caganer, it can’t be respect.