<P> The expansion of Scythian cultures, stretching from the Hungarian plain and the Carpathian Mountains to the Chinese Kansu Corridor, and linking the Middle East with Northern India and the Punjab, undoubtedly played an important role in the development of the Silk Road . Scythians accompanied the Assyrian Esarhaddon on his invasion of Egypt, and their distinctive triangular arrowheads have been found as far south as Aswan . These nomadic peoples were dependent upon neighbouring settled populations for a number of important technologies, and in addition to raiding vulnerable settlements for these commodities, they also encouraged long - distance merchants as a source of income through the enforced payment of tariffs . Sogdians played a major role in facilitating trade between China and Central Asia along the Silk Roads as late as the 10th century, their language serving as a lingua franca for Asian trade as far back as the 4th century . </P> <P> By the time of Herodotus (c. 475 BCE), the Royal Road of the Persian Empire ran some 2,857 km (1,775 mi) from the city of Susa on the Karun (250 km (155 mi) east of the Tigris) to the port of Smyrna (modern İzmir in Turkey) on the Aegean Sea . It was maintained and protected by the Achaemenid Empire (c. 500--330 BCE) and had postal stations and relays at regular intervals . By having fresh horses and riders ready at each relay, royal couriers could carry messages and traverse the length of the road in nine days, while normal travellers took about three months . </P> <P> The next major step in the development of the Silk Road was the expansion of the Greek empire of Alexander the Great into Central Asia . In August 329 BC, at the mouth of the Fergana Valley in Tajikistan, he founded the city of Alexandria Eschate or "Alexandria The Furthest". </P> <P> The Greeks remained in Central Asia for the next three centuries, first through the administration of the Seleucid Empire, and then with the establishment of the Greco - Bactrian Kingdom (250--125 BCE) in Bactria (modern Afghanistan, Tajikistan, and Pakistan) and the later Indo - Greek Kingdom (180 BCE--10 CE) in modern Northern Pakistan and Afghanistan . They continued to expand eastward, especially during the reign of Euthydemus (230--200 BCE), who extended his control beyond Alexandria Eschate to Sogdiana . There are indications that he may have led expeditions as far as Kashgar in Chinese Turkestan, leading to the first known contacts between China and the West around 200 BCE . The Greek historian Strabo writes, "they extended their empire even as far as the Seres (China) and the Phryni ." </P>

What goods were traded from the east (middle east) along the silk road to china