"No date is given to the story, but we have reason to believe that 'the country in the east' refers to China, known to the ancient Greek and Roman geographers as 'Serica', the country equated with sericulture."

Judging by archaeological excavations, the method for raising silkworm had reached Xiyu by the third century. In one case, Han-Dynasty wooden bobbins unearthed in the area were still wrapped around with gray and ocher-colored thread, emanating silken light after 1,800 years under the ground.

It is believed that Nestorian Christian monks were sent by the Byzantine Emperor Justinian I as spies on the Silk Road from Constantinople to China to steal the silkworm eggs, resulting in silk production in the Mediterranean.

However, the idea of sericulture as a heavily guarded secret has always been debated. Sun Ji, a Chinese historian and archaeologist, believes that the Chinese government in ancient times rarely did anything to prevent the leaking-out of silk-making methods but, rather, had pushed for their dissemination.

"The main aim of the Chinese rulers in their efforts to reach out through the Silk Road was always to demonstrate the strength and greatness of their empires. Acting in a shortsighted and self-interested way would only have undermined this goal."

Even if they did, the fact that silk-producing was being carried out nationwide would have made it virtually impossible to keep the secret within the country's porous borders.