Silk fabric was first developed in ancient China, possibly as early as 6000 BCE and definitely by 3000 BCE. Legend gives credit for developing silk to a Chinese empress, Lei Zu (Hsi-Ling-Shih, Lei-Tzu). The writings of Confucius recount that a silk worm's cocoon fell into the tea cup of the empress Lei Zu. Wishing to extract it from her drink, the young girl of fourteen began to unroll the thread of the cocoon. She then had the idea to weave it. Having observed the life of the silk worm on the recommendation of her husband, the Yellow Emperor, she began to instruct her entourage in the art of raising silk worms, thereby creating "sericulture". Lei Zu became the goddess of silk in Chinese mythology. In relation to this tale, only women were allowed to farm silk in China.
The earliest evidence of silk was found at the sites of Yangshao culture in Xia County, Shanxi, where a silk cocoon was found cut in half by a sharp knife, dating back to between 5,000 and 3,000 BCE. The species was identified as "bombyx mori", the domesticated silkworm. Fragments of primitive looms can also be seen from the sites of Hemudu culture in Yuyao, Zhejiang, dated to about 4,000 BCE, and scraps of silk were found in a Liangzhu culture site at Qianshanyang in Huzhou, Zhejiang, dating back to 2,700 BCE. Other fragments have been recovered from royal tombs in the Shang Dynasty (c. 1600 BCE - c. 1046 BCE).
Silks were originally reserved for the royalty of China but spread gradually through Chinese culture both geographically and socially. Silk rapidly became a popular luxury fabric in the many areas accessible to Chinese merchants because of its texture and luster. Silk was in great demand, and became a staple of pre-industrial international trade.
The first evidence of the silk trade is the finding of silk in the hair of an Egyptian mummy of the 21st dynasty, c. 1070 BCE. Ultimately the silk trade reached as far as the Indian subcontinent, the Middle East, Europe, and North Africa. This trade was so extensive that the major set of trade routes between Europe and Asia has become known as the Silk Road.
Allusions to the fabric in the Old Testament show that it was known in western Asia in biblical times. Scholars believe that starting in the 2nd century BCE the Chinese established a commercial network aimed at exporting silk to the West. Silk was used, for example, by the Persian court and its king, Darius III, when Alexander the Great conquered the empire. Even though silk spread rapidly across Eurasia its production remained exclusively Chinese for over a millennia.
Although silk was well known in Europe and most of Asia, China was able to keep a near monopoly on silk production. The monopoly was defended by an imperial decree, condemning to death anyone attempting to export silkworms or their eggs. Only around the year 300 CE did a Japanese expedition succeed in taking some silkworm eggs and four young Chinese girls, who were forced to teach their captors the art of sericulture. Techniques of sericulture were subsequently introduced to Japan on a larger scale by frequent diplomatic exchanges between the 8th century and 9th centuries.
Starting in the 4th century BCE silk began to reach the West by merchants who would exchange it for gold, ivory, horses or precious stones. Up to the frontiers of the Roman Empire, silk became a monetary standard for estimating the value of different products. Hellenistic Greece appreciated the high quality of the Chinese goods and made efforts to plant mulberry trees and breed silkworms in the Mediterranean basin. But it was not until 552 CE that the Byzantine emperor Justinian obtained the first silkworm eggs. He had sent two Nestorian monks to Central Asia, and they were able to smuggle silkworm eggs to him hidden in rods of bamboo. While under the monks' care, the eggs hatched, though they did not cocoon before arrival. The Byzantine church was thus able to make fabrics for the emperor, with the intention of developing a large silk industry in the Eastern Roman Empire, using techniques learned from the Sassanids--Persians who controlled the trade of silk destined for Europe and Byzantium.
Since the Chinese lost their monopoly on silk production, there was no longer a market for the most basic of their silk products. They did, however, maintain dominance in the luxury silk item market, and China continued to export high-quality fabric to Europe and the Near East along the Silk Road.