隋朝

For nearly four hundred years before the Sui, China had been broken. After the collapse of the Han and the brief, fragile reunion under the Jin, the country fell into the long age of the 南北朝, the Northern and Southern Dynasties, with rival regimes facing each other across the Yangtze, the north repeatedly ruled by dynasties of nomadic or mixed origin and the south by a succession of Chinese courts. Division was the normal condition of Chinese life for so long that a whole world of culture, religion, and politics had grown up around it.

The Sui ended it. In 581 the northern general 杨坚 Yang Jian seized the throne of the Northern Zhou and proclaimed the new 隋 dynasty. Then, in 589, his armies crossed the Yangtze, conquered the southern Chen dynasty, and reunited north and south under one ruler for the first time since the Jin. This was an achievement of the first magnitude: it restored the very idea of a single Chinese empire, the 天下 brought back under one house, and it set the template of a unified China that would, with interruptions, hold for the rest of imperial history.

杨坚, posthumously 隋文帝 Emperor Wen, was one of the great institutional builders of Chinese history, if a less celebrated one than the rulers who followed. Having reunified the realm, he set about rebuilding the machinery of a centralised state that had decayed during the centuries of division. He reorganised the central government into the structure of departments and ministries (the 三省六部, Three Departments and Six Ministries) that the Tang would inherit and that would govern China for centuries. He overhauled the law into a clearer, more humane code, reformed the currency, and restored the equal-field system 均田制 to put peasants on land and revenue in the treasury.

Most consequentially, the Sui began to replace appointment by aristocratic birth with selection by examination, the seed of the 科举 imperial examination system that would, over later dynasties, become the defining institution of Chinese government and the chief ladder of social mobility for a thousand years. Emperor Wen was famously frugal and hard-working, and under him the reunified empire grew rich and populous with startling speed. The granaries filled; the registers swelled. He left his successor a full treasury and a strong, orderly state, the foundation on which the next emperor would build, and overbuild.

The single most enduring Sui achievement is the 大运河, the Grand Canal, undertaken on a vast scale under the second emperor. The reunified empire had a structural problem: its richest agricultural land, the rice-growing south of the Yangtze, lay far from its political and military centre in the north. Moving grain and goods between the two by land was slow and ruinously expensive. The canal solved this by water. Linking and extending existing waterways, Sui labour created a continuous artificial river system connecting the Yangtze region to the northern capitals and the frontier, a network running for well over a thousand kilometres.

The human cost was immense. Millions of conscripted labourers were driven to dig the channels under brutal conditions, and the canal became a symbol both of the dynasty's power and of its cruelty. Yet the result outlasted the dynasty by more than a thousand years. The Grand Canal knit the Chinese economy into a single circulatory system, made it possible to feed northern capitals from southern harvests, and remained the spine of internal trade through the Tang, Song, Yuan, Ming, and Qing. It is one of the largest engineering works of the pre-modern world, and a UNESCO World Heritage Site today.

隋炀帝 Emperor Yang, who took the throne in 604, is one of the classic villain-emperors of Chinese tradition, the very name 炀 (a posthumous title meaning something like "the negligent and ruinous") a condemnation. He was not without vision or ability; the Grand Canal, the rebuilt eastern capital at Luoyang, and a brilliant court were all his. But he pursued grandeur with no regard for cost, and the burden fell on a population already strained by his father's mobilisations.

He built palaces and toured the empire in enormous, expensive progresses down his new canal. Above all, he launched a series of huge military campaigns against the Korean kingdom of 高句丽 Goguryeo, raising armies of staggering size and supplying them at colossal expense. The campaigns failed catastrophically, with vast losses, and they failed again when repeated. The combination of crushing taxation, endless forced labour, and ruinous, fruitless war broke the patience of the people Emperor Wen had so carefully enriched. By the mid-610s, rebellions were breaking out across the empire.

The collapse came fast. As revolts multiplied and the dynasty's armies fragmented into competing warlords, Emperor Yang withdrew to the south, to 江都 (Jiangdu) on the canal, abandoning the heartland. There, in 618, his own guard officers mutinied and assassinated him. In the same year his powerful relative and general 李渊 Li Yuan, governor of Taiyuan, took the capital Chang'an, set aside the puppet he had installed, and proclaimed himself emperor of a new dynasty: the 唐 Tang. After 37 years, the Sui was gone.

The parallel that every educated Chinese drew, then and since, was to the 秦朝 Qin: another short, harsh, brilliant dynasty that unified China and built astonishing works (the Great Wall for the Qin, the Grand Canal for the Sui), exhausted the people, and fell almost at once, leaving a long and glorious successor (the Han after Qin, the Tang after Sui) to enjoy the unity it had forced into being. The Sui became the textbook example of the dynasty that builds the road but does not get to travel it.

For a dynasty that lasted less than four decades, the Sui's imprint on Chinese history is extraordinarily deep, precisely because the Tang built directly on it. The reunified empire, the departmental government, the legal code, the equal-field land system, the divisional militia, the granary network, the rebuilt capital at Chang'an, and above all the Grand Canal and the embryonic examination system, all passed from Sui to Tang with little interruption. The 唐 dynasty's three centuries of cosmopolitan splendour rested on Sui foundations.

The Sui also fixed a lasting political lesson into the Chinese tradition: that reunification and great works are not enough, that a regime which exhausts its people through overreach forfeits the 天命, the Mandate of Heaven, however impressive its monuments. Emperor Yang became the standing example of the ruler destroyed by his own ambition, invoked for centuries as a warning against extravagance and against war pursued for glory. The dynasty that ended four hundred years of division and dug the artery of the Chinese economy is remembered both for what it built and for how quickly it fell.