So, there you are - Sicily, 1860, towards lunchtime. Garibaldi is heroically forging a modern democracy from blood, gunpowder and steel, but you're beginning to feel a bit peckish. Sod the Risorgimento, what's in the bread bin? Or go back further, to some humble Tuscan village around 1480, teatime. As the paint dries on Renaissance masterpieces all around, you repair to the local osteria for a quick bite and a flagon of Chianti. And what do you eat? Hearty, honest, country fare, of course; goats' cheese, maybe some dried ham, probably a few black olives - all, without doubt, accompanied by a generous slab of golden-brown ciabatta - pride of sun-dried, simple peasantry and folksy staple of Italian dinner tables since the Visigoths sacked Rome. Well, maybe not.

As in life, so in the realm of bread: all is not what it seems. For the ancestry of at least one form of ciabatta - the long, flat, rustic-looking loaf that takes its name from the Italian word for the slipper it supposedly resembles - reaches back not to the era of the Sistine Chapel, but to the days of Spandau Ballet. In short, the soul of the bread sold in Britain may well be thoroughly 1980s.

Since 1985, when Marks & Spencer introduced the ciabatta to British shoppers, we've been eating more and more of the stuff. Launched to capitalise on our rapidly evolving taste for Mediterranean rural cuisine, the bread soon became the Mother's Pride of the chattering classes. By the time Nessun Dorma rang out from Italia '90, it was one of the most popular food 'exotics'. Now it is an established part of the British baking repertoire and can be found, in one form or another, everywhere from major supermarket chains to stand-up bars.

On the face of it, this success is a little odd. Just look at the thing. For a start, it's a ridiculous shape. It's pointless slicing it as you would, say, a tin-loaf for a sandwich - a pair of the resulting bread slivers would offer little shelter for your bacon or cheddar, and most fillings would flop wildly at the fringes. Yet slicing horizontally can be a risky business, requiring advanced knife-skills to retain one's upper fingers. And then there's the name. If that's the shape of a slipper, then beef wellington is something you put on your feet when it's muddy outside. So why do we buy it? Part of the answer lies in Britain's love affair with Italian food; from our dank and stodgy island, the Mediterranean diet means purity, health and, above all, culinary tradition. For UK shoppers, Italy is sun-dried tomatoes, red pesto and lollo rosso - only it isn't, because you are as likely to find an Italian eating any of these as you are a Ukrainian eating chicken kiev. So there's the ciabatta, all over our land, bursting forth from ethnic wicker baskets and dressed up with olives and herbs as if freshly delivered by some flour-dusted Umbrian on a bike. How did we reach this state of affairs? Armed with the simple sword of truth, the Guardian followed the scent of baking bread. It was a journey that soon veered off into post-war geo-economics, rampant nationalism and led, ultimately, to contact with the global ciabatta industry's Mr Big.

July 1982. Israel invades Lebanon, Britain declares an end to hostilities in the Falklands, and, at a mill in Adria, a town near Venice, a small band of dedicated flour experts talk dough. One of their number, Arnaldo Cavallari, a miller in his late forties, is especially excited. For years, Rome could only look on, horrified, as large-scale baguette imports from France threatened to monopolise the lucrative sandwich market in Italy. It was time to hit back with an equally commercially viable product. After weeks spent testing new dough mixes and bake-times, refining and adapting existing regional loaves and using his own mineral- and gluten-rich flour, Cavallari came up with Italy's very own dedicated snack bread. He called it Ciabatta Polesano. It was hailed as the bread that saved Italy, and rocked the sandwich world.

'I invented the new ciabatta,' says Cavallari, loud and proud. 'I used a very soft, wet dough, with a lot of water - very watery. It's the best bread, of course. All my breads are made with natural things, so it tastes good. I am touching the sky I am so happy that it is so good, that it has done so well everywhere. But when I had invented it, I looked at it and I thought, 'What can I call it?' Then I thought that it is similar to a slipper, so I thought 'ciabatta'. For copyright, I registered the name ciabatta along with Polesano, the name of the area where I work. In 1989, I registered the name 'Ciabatta Italiana'. It's the best bread.' Cavallari's firm, Molini Adriesi, now licenses production of its ciabatta in 11 countries. However, according to at least one London-based Italian chef, a bread called ciabatta has been around for generations. 'People can say whatever they like,' says Cavallari. 'Someone could say they remember eating it in the 1940s, but they have got to come forward with the proof. There is no question of that recipe having existed before.' Armed with a new ciabatta recipe and hailed by some as the saviour of the Italian bread industry, Cavallari began to preach the message. He still does. 'My ciabatta is the taste of an old-fashioned bread,' he enthused down the phone line from his high-fibre headquarters. 'It reminds people of the older breads, the ones that were made with natural ingredients, no chemicals. On Wednesday afternoons, I teach a class in ciabatta, for people who want to know about it. They try it fresh, and say, 'Mamma Mia, this is good!' ' In Britain, ciabatta is almost universally manufactured on an industrial scale, mainly by the handful of large bakeries that also supply supermarkets with other Italian, and non-Italian, breads. This is not to say that mass production isn't any good - it's just, well, mass production.

Time to seek out Dan Lepard, consultant at Baker & Spice in Kensington - a compact bakery and shop that is making some of the finest loaves in London. Over the past few years, Lepard, 34, has become most favoured supplier of bread to high-table restaurants such as St John, Mezzo, the River Cafe, Le Gavroche and Zafferano. He has also become critical of industrial-scale bread production and the influence of Britain's baking establishment on our diet. What does he make of ciabatta, a new bread posing as an old one that is new? 'All of the useful breads - the ones designed to take a filling - are recent,' says Lepard. 'They have come about in the past 50 years. But there is nothing wrong with that, with invention. It's good to experiment. Granary, for example, was a brand name. Fine, it's a wonderful bread, but it was invented. In Italy, they wanted a bread you could fill, but it wasn't part of their tradition. So they made one. Here, they advertise that a ciabatta is made with extra-virgin olive oil. Do you need extra-virgin olive oil in it? No - but it helps it sell in Britain, and it also adds to the price.' Of all foods, says Lepard, none is so wrapped in fake history and general bunkum as bread. 'Bakers love myth. For example, there's the generation myth, that of being a long-established baker. But just because you're an 11th-generation baker doesn't mean you're any good. Or, at the turn of the century, it was the case that a Frenchman could just turn up in London and offer himself as a French 'expert baker' and he would be given a job on that basis. But then he would turn out to be rubbish.' Downstairs at Baker & Spice, the Victorian oven is fired up and glowing nicely. Lepard has been busy. A large tray containing a flat slab of damp, pale ciabatta dough waits to be baked. Its characteristic holes have formed, and the whole construction is slithery. So, a premium-priced bread whose key components are water and holes is becoming a bakery favourite? - surely not. As the temperature gauge hits 550 degrees, a fine spray of water is released into the oven. Through a peep-hole, the inside resembles a tropical inferno. The iron hatch is raised, the hapless proto-ciabatti are shoved in 2m, and the hatch lowered with a clunk. Twenty minutes later, the fully formed food is pulled out of the heat.

They went in creamy-grey and slopping and squarish; they came out golden and crispy and bow-tie-shaped. And they taste like the best you can buy. 'For around £10, you can get an excellent bread and a very good wine,' muses Lepard. 'And when it tastes so good, that's a fantastic meal in itself. It doesn't need anything with it.' Quite, but then thin, crusty, suspiciously stackable ciabatta is, let's face it, hardly a bread at all. And that is the real secret of its success: it is the perfect bread for people who don't like bread, and an endearingly imperfect bread for those who do.