Good walls make good neighbors
A TL where the Steppe nomads, those who would later become known as the Mongols, recognized the threat of a growing and uniting China under Qin Shi Huang- or at least, that's how it appeared to the Chinese; it's entirely possible that a Ghengis Khan was growing among them anyway. Therefore, when Liu Bang of the Han and Xiang Yu of the Chu rebelled against Li Si and Zhao Gao, Councilors of the Qin (all actual members of the Qin being dead or underage at this point), they attacked- resulting in all three dynasties dying.
This led to a complete fracturing of the Chinese system. A new Warring States period erupted- one with a very different result from the first one, and from the Spring and Autumn Period. This time, much effort was spent on alliances and fortifications- against the north, certainly, but also against each other. Several states- most notably, the Fang- did make large inroads towards unifying China, but for various reasons, they all failed. Additionally, they also faced warfare with the Mongols, the Koreans, the Burmese, the Vietnamese and the Mongols- all under different names, of course- who also shifted the alliances, turning China into something akin to western Europe during the middle ages.
This did have a number of effects across the rest of the world; most notably, it weakened the silk road, but also allowed for silkworms to be moved out of China. This shifted production westward- and it did, with production as far west as parts of Persia and Ethiopia, though more centered in India, where hybridizations with local silkworm moths led to both more broods in a year and increased pest resistance. By 1000 AD, Europe was divided politically between two major blocs: Gaul and the Holy Roman Empire. The Byzantines were small, but still surprisingly strong; the British Isles and Espania both were a collection of petty kingdoms supported by one side or the other (or possibly the Vikings, the Byzantines, or the Irish).
In China, meanwhile, borders began to stagnate. By 1200, in order to avoid war, most were formalized on an individual basis. Walls were built, walls extending and connecting the Great Wall- the walls of the title. Of course, more may be coming, as the TL is not near completion.
Things began changing around 1600. In Europe, the most pagan of peoples- the Norse, the Dutch, and the Welsh (also comprising those who, in OTL, would be the British, the Scots and the Irish) began ploughing the waves, looking for trade. Seeing the opportunity for trade, the various East Asian states also began building trade ships. Knowledge was exchanged. By 1800, China- as a collection of states- was beginning to see the power of industry. The Great Wall, dividing all of the Chinese States and helping protect them from invasion from each other, is considered one of the Wonders of the World. However, the Kingdom of Wales- famous for their black sheep and black silk moths, used to create austere, severe, terrifying clothes- was a strong rival power, and even the Kingdom of Ethiopia began building ships, helping others bypass the dying Byzantium through ports in modern-day Somalia.
The TL is most popular for showing the possible evolution of Chinese philosophy, as well as for doing something involving accurate knowledge of China in general.
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