"Those in the world who speak of the regularities underlying the phenomena, it seems, manage to apprehend their crude traces"
-Shen Kuo, Dream Pool Essays
Part I: 1086-1206
Low-cost loans for farmers and entrepeneurs. Nationalization of major agricultural and mining producers. Full land surveys to ensure proper taxation. Government-sponsored quality control in factories. A more practical and science-focused curriculum. These may seem like progressive reforms today, but the debate over them goes back to the Song Dynasty of China (960-1271). At the time, China was a center of monetary, military, and scientific advancement. During this dynasty, and specifically during the period in which the aforementioned reforms were introduced, paper money, movable type printing, the hydraulic clock, firearms, and the magnetic compass were invented. These reforms were eventually suppressed by court conservatives, but what if they had not been? What if science had continued to advance, and what if China had broken through into industrial revolution?
The point of divergence is the early death of Emperor Shenzong, who favored the New Policy reforms described above. In history, he died suddenly at age 30 in 1086. In this timeline, he reigns until 1109 (in line with the life spans of his immediate ancestors)(note: unless otherwise specified, everything beyond this point is in the alternate timeline). At this point, his son, Emperor Zhezong, took over without a period of regency (during which, in history, his regent suppressed the New Policy.) During his reign, the New Policy became established in the system of Neo-Confucianism. In 1136, Kai Yuehan, a provincial engineer, building on the discoveries of Su Song, made a breakthrough: a water wheel that could spin silk thread. The imperial court immediately recognized the value of Kai's invention and appointed Kai head of the Ministry of Works. Kai's invention thus spread throughout China and remained largely unchanged until the Yellow River flooded in 1194. By now, China had used the masses of silk that Kai had produced to recruit Xi Xia, Tangut, and Tibetan allies. A massive attack on the state of Jin was thus conducted, and succeeded in capturing all but the Northeasternmost Jin provinces. The ancient cities of Kaifeng and Chang'an were captured, and works built on the river. Several water-wheel factories were thus left dry when the river flooded and changed course. Natural gas wells and heating facilities were built near the abandoned factories(A.N.: Natural gas wells were invented in the 2nd century CE in China). The Muslim inventor Ma Fang soon observed that the steam rising out of these heating plants would turn water wheels. He thus devised a machine that would turn a water wheel with steam. All of these innovations were jealously guarded as trade secrets of silk production, but word got out. One of Kai's water spinners, adapted for wool thread spinning, was soon built in Nishapur, one of the major cities of the Khwarezm shahdom. Manichaean merchants, famed for espionage and with no great love for the Empire, soon also ensured that Kai's machines spread to Baghdad. By now, the works at Kaifeng, Nishapur, and Hangzhou were mass-producing firearms. The Hangzhou and Ningbo works, too, were also putting out high-quality steel for guns by 1207.
Inevitably among the books exported from China en masse to East Africa were some books of science. The city states of the African coast, with their contacts with Chinese Muslims, found out about Ma's invention by 1213, and about the process for steel production by 1249. A barbarian warlord who called himself "the Universal Leader" began attacking Chinese clients in 1205. As such, the Song encountered the Mongols far earlier. Being between the world's greatest industrial power and the world's best organized war machine, this would be a battle for the ages.
"It was here that Chinggis Khan was born. As he was born, he emerged clutching a blood clot the size of a knucklebone die"
-The Secret History of the Mongols, tr. Cleaves
Part II: 1206-
A great empire such as the Song did not take kindly to invasions of its allies. The Jin remnants, however, took this opportunity to ally with the Mongol hordes. The presence of the Jin marked these men of the steppe for Chinese retribution. A detachment of 150k musketmen, with Tanggut, Khitan, and Xi Xia auxillaries, marched against the Mongols. The Mongols continued to raid deep into China, at one point sacking Beijing, but in 1208, the Army caught up to them. The auxillaries distinguished themselves well; the Mongols pursued their traditional tactic of feigning retreat, then advancing, but the disciplined Song musket line held firm. This quickly degenerated into a rout as the auxillaries pursued the Mongols back to their homeland, capturing horses and burning yurts all the way. By 1211, the Universal Leader had been crushed, and his dreams of conquest left unfulfilled. With the passing of the Mongols, steppe nomads largely ceased to be an important factor in world history.