Silk is a delicate, lustrous cloth spun from the cocoons – the soft protective cases – that mulberry silkworms, the larvae of a particular moth, build around themselves. Its discovery is wrapped in legend. The tale most often repeated concerns Ai Ling, consort of the emperor Shenhuang, who is said to have governed China around 3000 BC. Strolling one day through the palace gardens, she noticed that several mulberry trees were being stripped bare by silkworms, and she gathered up a handful of their cocoons before settling down to rest. As she did so, one of the cocoons slipped from her grasp into the hot water beside her, and the warmth began to loosen it into a single slender filament. Finding that she could wind this thread about her fingers, she asked the emperor to let her raise silkworms on a stand of mulberries, and in time she built a spindle by which the fibres of a cocoon could be drawn off and twisted into a strand strong enough for weaving. How much of the story is genuine no one can say, yet there is no doubt that the Chinese have cultivated silk for thousands of years.
In the beginning, the rearing of silkworms was a sacred duty carried out only by priests, who supervised each stage from the feeding of the worms to the weaving of the cloth. Silk soon became a badge of rank, and in the earliest times only the nobles were allowed to dress in it; that restriction eased so slowly that not until much later dynasties could even the common people wear it. So greatly was the fabric valued that it also circulated as a kind of payment: officials drew their salaries in it, and farmers were permitted to meet part of their taxes with lengths of cloth rather than in coin. Rulers likewise sent it abroad as gifts of state. Bowstrings, fishing lines, the strings of instruments and even writing surfaces were fashioned from it. Among the most striking survivals is an early silk map, the oldest yet uncovered, recovered from the tomb of a nobleman thought to have died around 165 AD.
The craving for so rare a cloth in time gave rise to the celebrated trading route we now call the Silk Road, which carried silk out to the west and brought horses, along with gold and silver, back to the east. The road took its name from the single commodity that counted for most upon it, a fabric prized above gold itself. Stretching more than 6,000 kilometres between eastern China and the Mediterranean, it followed the line of the Great Wall, climbed the Pamir ranges, passed through what is now Afghanistan and reached the Middle East, where Damascus served as a great market; from there the wares were carried by ship across the sea. Scarcely any trader covered the whole distance, the goods passing instead through the hands of one middleman after another.
The mulberry silkworm being found nowhere but China, that land stayed for centuries the sole source of silk anywhere on earth. It was through the Byzantine Empire – master of the Mediterranean world of southern Europe, North Africa and the Middle East from 330 to 1453 AD – that knowledge of the craft at last leaked abroad. In one story, a pair of envoys acting for the Byzantine emperor are said to have smuggled silkworm eggs into Constantinople, today's Istanbul, in 550 AD, tucked away inside hollow walking canes. The Byzantines, though, proved every bit as close with the secret as the Chinese before them, and the weaving and selling of silk stayed a tight monopoly of the crown for hundreds of years. Not until the Arabs swept over Persia in the seventh century did its magnificent silks pass into other hands.
From Persia the art travelled on, spreading through Africa, Sicily and Spain in the wake of the Arab conquest. By the tenth century the Spanish region of Andalusia had grown into Europe's foremost centre of silk-making. Within a few hundred years, though, that lead had passed to Italy, whose merchants in Venice dealt heavily in the cloth and drew silk-growers to settle among them; even today the silk finished in the northern town of Como is held in high esteem.
In Europe, silk-making slid into decline once the nineteenth century and its factories arrived. Among the causes was a flood of cheaper Japanese silk, which the newly opened Suez Canal did much to speed on its way. A further blow landed in the twentieth century, when artificial fibres – polyester and the like – were increasingly substituted for silk in such goods as parachutes and stockings; the two world wars, meanwhile, severed Japan's supply of raw material and hurt the European trade still more. Once peace returned in 1945, Japan revived its industry with sharper methods and better raw silk, and right up to the 1970s it stood as the foremost producer of raw silk and very nearly its only exporter of any weight. Since then the lead has swung back to China, once again the world's principal maker and shipper of raw silk and silk yarn alike. Worldwide output today runs to some 125,000 tonnes a year, of which China accounts for very nearly two-thirds.
