The Silk Road World

If the Islamic world was the age's great library and Africa its unjustly forgotten gold, the eastern end of Eurasia held its true superpower, and its name was China. Under the Tang and then the Song dynasties, spanning most of these centuries, China was almost certainly the most advanced civilization on the planet, and it was quietly inventing the modern world piece by piece. Consider the list, and consider that any one item would mark a civilization: they invented printing, first with carved blocks and then, under the Song, with movable type, so that books could be produced by the thousand. They invented gunpowder, which would one day remake war on every continent. They perfected the magnetic compass, which would open the oceans. They issued the world's first paper money. They built water-driven mechanical clocks of extraordinary sophistication, cast iron in blast furnaces on a scale Europe would not equal for six centuries, and ran their vast bureaucracy through a civil service selected, in principle, by competitive written examination, a meritocracy of the brush that would not be seriously attempted in the West until modern times. The Song capital of Kaifeng held well over a million people. By any measure that mattered in the year 1000, China stood at the very threshold of an industrial revolution, seven hundred years early.

And China did not stand alone; it stood at one end of the great artery that gave this chapter its name. The Silk Road was never a single road but a shifting web of caravan tracks and sea lanes running the whole width of Asia, and along it moved not only silk and spices and porcelain but ideas, faiths, and inventions. Buddhism traveled it from India into China and Japan; papermaking leaked westward along it toward the Islamic world and eventually Europe; and at its far western end, the Byzantine Empire, the surviving eastern half of Rome, guarded Constantinople, the greatest Christian city on Earth, and preserved through all these centuries the Greek learning that the Latin West had lost. Then, in the thirteenth century, the whole of that vast overland network fell under a single power for the first and only time in history. The Mongols, exploding out of the steppe under Genghis Khan and his heirs, built the largest contiguous land empire the world has ever seen, from Korea to Hungary, and, having conquered it, they policed and reopened the trade roads so completely that the era is remembered as the Pax Mongolica, when, it was said, a virgin with a sack of gold could ride the length of Asia unharmed. It was in that reopened world that a Venetian named Marco Polo could travel to the court of Kublai Khan and come home with tales Europe could scarcely believe.

But the artery that carried such wealth and wonder carried something else as well, and here the great dark theme of this book returns with a vengeance. A connected world is a shared world, and it shares its diseases. Twice in these centuries a pestilence rode the trade routes into catastrophe. In the sixth century, on the heels of a mysterious global cooling in the year 536, when a scholar recorded that the Sun gave its light without brightness through a whole year and famine spread from Ireland to China, the first great plague pandemic struck the Mediterranean and killed perhaps a third of its people. And in the fourteenth century came the Black Death, which boiled out of Central Asia and followed the very Mongol trade roads west, killing between a third and a half of everyone in Europe and tens of millions more across the Islamic world and Asia in a handful of horrifying years. It is exactly the cascade physics we watched destroy the Bronze World, now operating on a far larger and more connected medieval planet: the same dense web of exchange that carried the silk and the printing and the paper money carried, with perfect efficiency, the flea and the bacterium that would empty half the towns of a hemisphere. Interconnection is the age's glory and its curse in a single breath, and that double edge, we will find, has not dulled in the slightest by our own time.