A century ago, hell let loose game the eastward expansion of the Empire met the great sea of grass in the centre of the continent. Beyond that, with no farmland where the legions could forage, they could conquer no more. They fortified their most recent acquisitions, the great trading cities on the steppe's edge, confident that the disorganized horse tribes beyond the frontier posed no major threat. Khuzaits, Nachaghan, Arkits, Khergits, Karakhergits - imperial officials barely even bothered to learn the names of the various clans and peoples, except when it was necessary to turn one chief against another with a bribe, or remove a rising khan with a vial of poison.
The steppe tribes were well aware how the Empire toyed with them. But they were jealous of each other, and an imperial title, a princess bride, or a chest of gold could give them a slight edge in the endless struggle for prestige and precedence. They raided, traded, took protection money to "escort" caravans across the steppe, and left the game of conquest to the settled peoples. Two generations ago, however, something happened far away to the east - a change in the winds, perhaps, or some terrible but distant conqueror - and the horse clans were set in motion. New tribes pushed westward, seeking fresh pastures. Unwilling to be crushed in the middle, the clans nearest the empire formed a confederacy under Urkhun the Khuzait. They caught the Empire in a moment of overconfidence. A force of legions was annihilated, the trading cities capitulated, and Urkhun's confederacy was now a khanate.
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