To mention what is called the “Silk Routes” today is to evoke more than two thousand years of history on two continents, Europe and Asia. Naturally, over such a long period and such vast territories, hundreds of products were transported, exchanged, stolen, conquered, transferred, in short, from one country to another. For some of these products, the very source of the raw materials and the techniques of production themselves were transferred.

Everyone knows that the Chinese invented paper, printing, gunpowder and the compass—great technological advances; as for the last three, their transmission throughout the world goes back only to the Crusades, which is quite recent. Here we are interested in transfers that are less known and more ancient, the most ancient for which precise records exist, starting from the time of the “opening” of the silk routes, which, according to Chinese classical history, was during the second century B.C. We shall stop around the eleventh century A.D., at the time of the Sung dynasty. This period includes the two most interesting epochs, in our opinion, in the history of the exchanges on these routes: the Han dynasty (from 206 B.C. to 220 A.D.) and the Tang dynasty (618-907), epochs whose time frames encompass the Western Roman empire, the Eastern Roman empire, the kou-chau empire, Sassanid Persia, and the first centuries of Islam.