So here's the deal: far to the west are a nest of squabbling kingdoms, vicious, vigorous, fratricidal. From them come inexplicable wars, new technologies, sturdy manufactured goods, and a flood of gold and silver, which they claim to have mined from another, newer world. The game isn't really about them.
Far to the east are the ancient empires, serene, cruel, and implacable. From them come strange religions, silk and spices, drugs and porcelain, lacquer and tea. The game isn't really about them, either.
Between them lie about three thousand miles of desert, steppe, taiga, hills, mountains, and tundra. And through that landscape runs a road.
In reality, by the later seventeenth century - which is the closest thing that ATWC has to a historical reference point - the great days of the silk road were over. But never mind that. This is a silk road of the mind, endlessly unfolding across wilderness after wilderness, kingdom after kingdom; it will carry you from oasis to oasis, caravanserai to caravanserai, and your companions on the journey will be wild-eyed mystics and scholarly ascetics and wary gold-toothed traders and the endless clinking of the camel's bells. If you set off in spring, you might reach the road's end before winter. You will not be the same person who set out. The wind on the high plateaus will have purified you. The desert will have burned all that is not essential from your soul. In the freezing nights, under enormous skies mad with wheeling constellations, you will have experienced strange moments of clarity. You will never be quite the same again.
The road winds through lands which are otherwise pathless. Step off it and you are lost; the landscape will eat you; a million square miles of emptiness will yawn open like a single immense mouth and you will be devoured. Possibly literally: there are monsters out there, and beasts of prey, and wild and savage cannibal tribes whose hooting incantations can turn the day to night. Keep to the road. Many holy men walk on the road, alongside the merchant caravans. The gods will protect their own.
For the gods seem very close, out here, in the wild places; and while you might not know who to side with when the holy men sit down at night to begin one of their interminable disputations about the nature of divinity, you know that something is out there, looking down at you from the orb of the sun by day and the curve of the moon by night. You can almost hear it, on the wind, in the chattering of the unfamiliar birds; a voice, a voice calling out of the landscape, a voice that is not like the voices of men. No wonder religions flourish along the road; and in each of the golden oasis-cities, each one more spectacular than the last, you can find the shrines and temples of all the world's great religions, their saints and imams and bodhisattvas beckoning with ivory hands, lapis lazuli eyes raised towards the vault of heaven...
Religions flourish along the road, yes: but empires die. Armies stumble and starve out here, far from their rice paddies and wheat fields; and whenever some horse-lord with aspirations to civilisation rides in off the steppes and sets up a kingdom of his own, it only seems to be a matter of time before some even more savage horde sweeps in and brings it all crashing down. Each day, as you ride, you see the graves and the ruins, scattered to either side of the road: the fallen towers, the broken arches, the temples and palaces sinking into the sands. Sometimes the young men rush off to scavenge in the ruins, hoping to find old treasures. Sometimes they do not come back.
It is high time you set out to travel the road. It is high time you saw the great temples of the oasis-cities for yourself. You can sign on as a caravan guard, perhaps, or maybe scrape together a little money with which to buy silk and tea and opium, in the hope of selling them for a small fortune in the west. You might get lucky in the old ruins. Yours might be one of the caravans that the wild folk and the monsters leave unmolested. It might.
But beware: for at the very heart of the road, a once-great city has fallen into wickedness. Pay your tolls without complaining. Camp far from its ruinous walls. Keep your musket clean and your long knives handy. Do not set foot within its gates.
Travel with as many holy men as possible. Their company will protect you in those evil days when you must walk beneath the shadows of the towers of the Wicked City.