Around 138 BC, a Chinese court official named Zhang Qian rode west out of Han territory on a diplomatic mission and promptly spent about a decade as a prisoner of the nomadic Xiongnu. When he finally returned to the emperor, his mission had failed but his report was priceless: beyond the deserts lay organised kingdoms in Central Asia with cities, markets and, most excitingly for a cavalry-hungry empire, the magnificent "heavenly horses" of the Ferghana Valley. Chinese envoys and merchants soon followed his route west. Zhang Qian is remembered in China as the trailblazer of what the world now calls the Silk Road.
Except it was never a road, and silk was only part of the story. The name — Seidenstraße — was coined as late as 1877 by the German geographer Ferdinand von Richthofen. What actually existed was a shifting web of caravan tracks and sea lanes stretching several thousand miles between China and the Mediterranean, threading oasis towns around the Taklamakan Desert, over the Pamir mountains, through Samarkand and Persia to the ports and markets of the Levant. Almost no trader travelled the whole way. Goods moved in relays, marked up at every stage, passed between middlemen who might have only a hazy idea where their merchandise ultimately came from. The greatest of those middlemen were the Sogdians, an Iranian-speaking people from around Samarkand whose language became a lingua franca of the caravan routes.
What moved along it
Silk flowed west because only China knew how to make it, and the Romans developed an expensive addiction to it. Moralists fumed: Seneca complained that silk garments concealed nothing, and Roman writers fretted about gold draining east to pay for luxury. China guarded sericulture — the cultivation of silkworms — as a state secret for centuries. According to the historian Procopius, the monopoly was finally broken around the 550s AD, when monks smuggled silkworm eggs to the Byzantine emperor Justinian concealed in hollow canes, seeding a silk industry in the Mediterranean world.
But the road's real cargo was ideas. Buddhism travelled it from India into Central Asia and China, leaving a trail of monasteries and cave temples — most spectacularly the Mogao Caves at Dunhuang, a desert crossroads where a sealed chamber discovered around 1900 yielded tens of thousands of manuscripts. Among them was the Diamond Sutra of AD 868, the world's oldest dated printed book, acquired for Britain by the archaeologist Aurel Stein. Nestorian Christianity, Manichaeism, Zoroastrianism and later Islam all moved along the same tracks. So did technologies: papermaking spread westward from China into the Islamic world after the mid-eighth century — tradition links it to Chinese prisoners taken at the Battle of Talas in 751 — and eventually transformed Europe.
The routes worked best when strong empires guaranteed the peace: the Han and Rome bookending the ancient network, the Tang dynasty at its medieval height, and above all the Mongols. The thirteenth-century Pax Mongolica — one vast empire from China to Eastern Europe — made trans-Eurasian travel safer than it had ever been, which is how a Venetian merchant family like the Polos could reach the court of Kublai Khan. Marco Polo's account of his travels, dictated to a romance writer while in a Genoese prison, became medieval Europe's window on the East, and a copy of it, annotated in his own hand, later belonged to Christopher Columbus.
The dark passenger
Connectivity cut both ways. In the 1340s the Black Death moved out of Central Asia along the trade routes, reaching the Black Sea and then, via Genoese ships, the Mediterranean — going on to kill perhaps a third or more of Europe's population. The same arteries that carried sutras and silk carried Yersinia pestis.
The overland network faded rather than died. The Mongol empire fragmented, and from the fifteenth and sixteenth centuries European sailors — Portuguese ships rounding Africa, then the great East India companies — made bulk sea transport cheaper and faster than any camel caravan. The oasis cities dwindled into romantic backwaters until nineteenth-century explorers and archaeologists, chasing Richthofen's evocative coinage, rediscovered them. Today stretches of the routes are UNESCO World Heritage listed, and the name has become shorthand for any grand connection between East and West. The deeper lesson survives every quiz question about it: globalisation is not a modern invention. Two thousand years ago, a bolt of Chinese silk could end up on a Roman shoulder, and neither the weaver nor the wearer knew the other existed.
Quiz nuggets
- The term "Silk Road" was coined in 1877 by German geographer Ferdinand von Richthofen.
- Han envoy Zhang Qian's missions from 138 BC opened China's routes to Central Asia.
- Monks reputedly smuggled silkworm eggs to Byzantium in hollow canes around the 550s AD, breaking China's silk monopoly.
- The Diamond Sutra (AD 868), found at Dunhuang, is the world's oldest dated printed book.
- The Black Death of the 1340s spread westward to Europe along Silk Road trade routes.