China: A History. John Keay

and a new direction given to Han’s expansionist momentum. Instead of pushing ever farther north into the unrewarding wastes of Mongolia, Chang’an’s troops would veer west and set their sights on the flourishing states of central Asia, as reported by Zhang.

      Initially Zhang’s discoveries had served as a distraction. In the course of his western odyssey, the explorer had crossed the deserts of Xinjiang, scaled the bleak Pamirs and descended to both the Syr Darya (Jaxartes River) and Amu Darya (Oxus River). The region along the former was called ‘Dayuan’, otherwise Ferghana and now eastern Uzbekistan, that along the latter ‘Taxia’, otherwise Bactria or northern Afghanistan. Since the Yuezhi had just overrun Bactria, they showed no interest in returning east of the Pamirs to oblige Chang’an in its feud with the Xiongnu. Their future lay south of the Himalayas, where they would be known as the Kusana (Kushan), would found one of northern India’s greatest empires, and in the first century AD would repay Zhang’s visit by sending to China the first Buddhist missionaries. But as yet ignorant of ‘the Enlightened One’, the Yuezhi in the early 120s BC opened explorer Zhang’s eyes only to the importance of the strange world into which he had blundered.

      Had it not been for his decade-long detention by the Xiongnu, Zhang would have found Greek-speaking kings with names like Euthydemus and Menander still ruling in Bactria. Relics of Alexander the Great’s expedition, these Bactrian kings had been ejected by the Yuezhi in 130 BC, just months before Zhang’s arrival. Their magnificent gold and silver coinage was still in circulation and surprised Zhang by its novel use of portraiture. Each coin, he reports, ‘bore the face of the king [and] when the king died, the currency was immediately changed and new coins issued with the face of his successor’. Such a practice had never been known in China; since it could be construed as ennobling commerce and demeaning the sovereign by association with it, nor would it be.

      West of Bactria stretched the great kingdom of ‘Anxi’, otherwise Parthia or Persia (Iran), where the Seleucids, also legatees of Alexander’s empire, had earlier been overthrown by the Parthian Arsacids; this Anxi extended to what Zhang calls ‘the western sea’, which is thought to be the Gulf rather than the Mediterranean. East of Bactria, the kingdom of ‘Shendu’ was of more interest. While exploring the Bactrian bazaars, Zhang had noticed ‘cloth from Shu [Sichuan] and bamboo canes from Qiong [also in Sichuan]’, both of which were said to have been imported via ‘Shendu’. Although some of explorer Zhang’s place-names are hard to identify, there is no question that ‘Shendu’ was India; its inhabitants ‘rode elephants into battle’ and even the Romans knew the country as ‘Sindu’ (after the Sind, or Indus, River). Since it was said to be several thousand kilometres east of Bactria, Zhang reasoned that it must ‘not be very far away from Shu’. Silk cloth and bamboo canes must therefore be reaching India direct from China’s extreme south-west.

      Of all Zhang’s revelations, this was the one that had at first excited the most interest in Chang’an. As his ten years of Xiongnu captivity had demonstrated, access to central Asia was as yet fraught. Across the deserts of Xinjiang the Xiongnu controlled the route north of the ‘Great Swamp’ (nowadays the salt desert of Lop Nor), while Xiongnu allies, the proto-Tibetan Qiang, controlled that south of it. Only the cane-and-silk route from Sichuan to India and Bactria looked to offer a way of circumventing both. When Zhang had proposed that he lead a secret expedition to explore it, ‘the emperor was delighted’.