The Southern Song was the summit of refinement — rich in trade, exquisite in painting, poetry, and porcelain, with cities beyond anything the Europe of that day could show. The idol, however, was not the luxury but an institution of its own building: the tribute system, which bought peace from the steppe neighbors with silver and silk. Payment was built into the structure of the state as a substitute for defense — and a means raised into the order of things left helpless the one who leaned upon it.
The collapse came from the sea. By 1279 the Mongol Yuan state under Kublai was grinding down the last of the Song forces. The end came at Yamen: a Song admiral chained some thousand ships together into a single floating rampart to shield the court and the boy emperor — and that motionless mass became a trap. The Yuan fleet, a tenth its size, shattered it. When all was lost, a minister took the last emperor, a boy of eight, in his arms and leapt with him into the sea. The House of Zhao was extinguished, and for the first time in history the whole of China lay under the rule of a foreign dynasty.
The captivity was not exile but subjugation at home. The Yuan dynasty was established; the native Chinese elite was pushed from power, and society was stratified into an ethnic-caste hierarchy in which the conquerors and their allies stood above the conquered. It was the same dynastic cycle of the "Mandate of Heaven," but with a bitter novelty: bondage took the form of foreign dominion over the whole country. A people that for centuries had been the center of its own universe now lived on the lower rungs of an alien order, on its own soil — and no longer its master.
The return ripened from within. In the fourteenth century a wave of rebellions overthrew the Yuan, and in 1368 the Chinese Ming dynasty rose. The "Mandate of Heaven" lay once again in native hands — not bestowed from without but wrested from below by those whom a century had held down. The law of history kept its word here too: foreign dominion, however solid it looked, proved a time of captivity, not the end of a people. The refinement that had failed to save the Song was smelted into a new hardness — the price of return had been learned.