Writing in the third quarter of the first century CE, the Roman author Pliny complained: "At the smallest reckoning 100 million sesterces [of gold=16,660 English pounds] is the sum which every year India, the silk-growing country of northern China, and the Arabian peninsula take from our Empire. Such is the cost to us of our exquisites and our women." Whether in fact the Roman Empire was being bankrupted by female tastes for luxury, its eastern trade was significant. Indeed this was precisely the period when the Han Empire had been aggressively expanding into Central Asia and when huge quantities of Chinese silk were being shipped westwards.

There were several routes to the East. In the north, trade passed through the Caucasus, crossed the Caspian Sea and then went up the Amu Darya (Oxus) river. Of much greater significance was the route from the Mediterranean through Damascus and the desert city of Palmyra to Mesopotamia. From there, merchants either could sail down to the Persian Gulf or head northeast through Parthia to Central Asia. A Macedonian merchant Maes Titianus described this route up to an inner Asian location known as the Stone Tower, where the exchange of goods would take place with merchants coming from China. The third of the routes was via the Red Sea and on to India. On the western end of this route, the trade could go up through Petra (in today's Jordan) to Syria or directly across to the Mediterranean. Alternatively, merchants crossed from the Red Sea to the Nile and on to the great city of Alexandria.

The sea route to India really opened up in the first century BCE with the discovery of how the monsoon winds would allow direct passage across the Indian Ocean and back, thus avoiding the coastal route with its dangerous reefs and pirates. The classic description of these sea routes is a book written in the first century CE, the Periplus of the Erythraean (Red) Sea. Its author was at least vaguely aware of China: "...Somewhere on the outer fringe, there is a very great inland city called Thina from which silk floss, yarn and cloth are shipped by land via Bactria to Barygaza [i.e., down through northwest India to the coast] and via the Ganges River… It is not easy to get to this Thina; for rarely do people come from it, and only a few."

The importance of any one of these routes depended on the political landscape in the Middle East. One factor was the rise of Parthia, occupying northern Iran and reaching its peak in the first century BCE. The Parthians even managed to take Jerusalem before being driven back by the Romans, who then aggressively extended their control of the western end of the trade routes in the first and second centuries CE. In particular, the Romans established suzerainty over the Nabataens, the rulers of Petra, and then in 115 CE under Emperor Trajan were able briefly to hold Ctesiphon, in the Parthian heartland. Trajan built a major road connecting Damascus with the Gulf of Aqaba and the Red Sea. The Roman architectural legacy from this time in the Middle East was substantial.

Significant events were also taking place on the eastern borders of Parthia. A Chinese ambassador reached Parthia in 97 CE and reported on Parthian efforts to confine the trade to the overland route in order to avoid paying the customs duties required in taking the circuitous sea route around Arabia. In 166 CE another Chinese source reported that Roman merchants, who apparently claimed they were ambassadors from the Emperor, reached one of the Chinese ports. The trade along the silk roads was undoubtedly promoted by the emergence of the Kushan Empire as the most powerful state astride the routes reaching up into Central Asia and crossing Afghanistan and northwest India.

Roman trade with India is documented by numerous finds of Roman coins along the Indian coast and by other objects along the overland routes. For the Romans, spices may well have been even more important than silk, and the major source of the spices was South and Southeast Asia. The penetration of Classical art into Kushan territories clearly was not simply the legacy of the Graeco-Bactrian kingdoms that succeeded the empire of Alexander the Great in the East. There was a continuing influx of objects decorated with Classical motifs; Roman temples were built in at least one or two locations.

The patterns established by the Roman trade with the East would continue long after the fall of Rome and the rise of the Sassanians, who replaced the Parthians. The "silk routes" ran overland and by sea, their important branches were both east-west and north-south, and the products included much more than silk.

--Daniel C. Waugh