This one is in the setting of S.M. Stirling's work 'Conquistador.' Although the book is mostly a high-tech wild-west story, there is some scant mention of the outside world.
........
In this world, Alexander the Great was lucky enough to leave longer, successful to return to the west to conquer Carthage, and wise enough to know when to quit. Alexandrian Dynasties connected the world from the Bay of Bengal to the Straits of Gibralter for a few centuries as they slowly difted apart. For the next two thousand years, human progress is largely confined to the Middle East. Trade routes extend as far as the British Isles, Madagascar, and the Philippines, but essentially only the core of the Alexandrian Empire ever approaches anything resembling a renaissance-level of development-- spurred on by the invention of the priting press and paper in the 1800s. The Medditerranean and Black Sea perimeters, along with North India, are seen as provincial backwaters of civilization by the Greek-speakers in Mesopotamia, which continues to be the wealthiest and most densely populated part of the world.
One of the biggest factors in this world's apparently slow development has been the destruction of anything resembling our world's Chinese civilization from a very early date. Triggered by a very different situation in Persia, Red and Blonde-haired Tocharian peoples inhabitaing the Xinjiang migrate east. Large-scale invasions into China in the 3rd century B.C. dramatically change the political landscape, including preventing Qin Shi Huangdi from being born. Chinese unification is thus still-born. The Tocharians, like the Anglo-Saxons of our world, are forever referred to by the largest two of their tribes 'Selang' and 'Arsi.' (which are known to specialists in our world as Tocharian B and Tocharian A respectively) Although assimilated into the cultures they conquer (meaning that by modern times, their descendants look very different any culture in our world but would probably still be vaguely Chinese or Korean in appearance, sometimes with brown hair), their language becomes the language of Northern and Central China. They continue to recognize Chinese thinkers like Confucious or Lao Tzu [Actually, since Confucianism does not undergo state-sponsored repression, the ideology grows and develops in different ways but never comes as close to a religion as it did in our world] and fully embrace ancestor worship, but remnants of their chariot-driving twin deities (thunder and lightning) persist. The Horse and Cow take on a prominence not found in our China, leading to China's rather unique taste for pork not forming and rather more dairy products in locals' diets. Both the Selang-Arsi and the Han people they intermix with continue to be clan-oriented in the absence of any large-scale state building projects. As the Selang-Arsi spread north, they assimilate Machus and the peoples of the Korean peninsula.
A second group set of peoples migrates into the North China Plain in period from 200 A.D. to 600 A.D. These are North Iranic Peoples- relatives of the Scythians (whose closest modern-day equivalents in our world would be the Ossetians), populating a region streatching from the Dneiper to the Altai mountains. With a very different Middle East and a partially Hellenized Bactria invading Sogdiania in Central Asia, much of the medieval horse archer steppe horde migrations has gone rather more uniformly west-to-east in this world. Though numbering in hundreds of different tribes (and absoring non-Iranic steppe peoples such as the Turks and Mongols) these people unify on the steppes (referred to by residents of the Middle Lands as the people of 'Kang,' originally a term connotating just Sogdiana). When this land is conquered by the Greek-speaking Bactrians, there is just enough push to bring about a second great migration into the Middle Lands. The Kang leave an even smaller genetic inprint on the Middle Lands, but in the central part of the country (still contested between the Selang-Arsi and the Han) one of the Iranic languages becomes the common tongue of the masses.
The Middle Lands then, are not an Empire. But there is a common civilization of sorts, one which solidifies in the next thousand years. Following Confucius and Lao Tzi, new generations of philosophers write treatistes on harmony, duty, and nature (legalism, meritocratic tests for officials, and bureacracy all remain noticeably absent). The earliest forms of Classical Chinese, though not a spoken language for long, continue to be the primary written language of all the local peoples. Buddhism, Hinduism, Hellenization, and any additional foreign influences, are resisted as the Selang-Arsi, Kang, and Mian (the large Han state that eventually forms in the South) close ranks as the true 'natives' of the Middle Lands.
By 1975, history has moved forward, though rather differently. The Middle Lands remain technologically in the Iron Age, equivalent in the most advanced parts (say, on the *Korean Peninsula) to OTL Rome in the 3rd Century A.D. (and maybe with worse aquaducts and roads), and elsewhere roughly as technologically advanced as ancient Persia. The printing press, paper, and the compass exist, but have only been invented in the Greek Middle East, and this world has nothing along the lines of gunpowder, steel, or windmills. The Selang Arsi and Mian both do have improved wooden-navies scattered across the East China Sea. The Selang Arsi attempted to conquer the even more primitive land of Yamato (ruled by its own God-King), starting in 1555, but after four centuries of conflict and slow-rising up of the natives, the Selang-Arsi have (mostly) been kicked off the islands by angry locals.
In 1975, U.S.-made helicopters which have been transported from another dimension, land down in a small Selang-Arsi fort town at the sight of what in our world would be Beijing. The strange humans exiting them are hailed as gods by some, but the local king quickly realizes that they are at worst potential conquerors and at best potential trade partners...
........
In this world, Alexander the Great was lucky enough to leave longer, successful to return to the west to conquer Carthage, and wise enough to know when to quit. Alexandrian Dynasties connected the world from the Bay of Bengal to the Straits of Gibralter for a few centuries as they slowly difted apart. For the next two thousand years, human progress is largely confined to the Middle East. Trade routes extend as far as the British Isles, Madagascar, and the Philippines, but essentially only the core of the Alexandrian Empire ever approaches anything resembling a renaissance-level of development-- spurred on by the invention of the priting press and paper in the 1800s. The Medditerranean and Black Sea perimeters, along with North India, are seen as provincial backwaters of civilization by the Greek-speakers in Mesopotamia, which continues to be the wealthiest and most densely populated part of the world.
One of the biggest factors in this world's apparently slow development has been the destruction of anything resembling our world's Chinese civilization from a very early date. Triggered by a very different situation in Persia, Red and Blonde-haired Tocharian peoples inhabitaing the Xinjiang migrate east. Large-scale invasions into China in the 3rd century B.C. dramatically change the political landscape, including preventing Qin Shi Huangdi from being born. Chinese unification is thus still-born. The Tocharians, like the Anglo-Saxons of our world, are forever referred to by the largest two of their tribes 'Selang' and 'Arsi.' (which are known to specialists in our world as Tocharian B and Tocharian A respectively) Although assimilated into the cultures they conquer (meaning that by modern times, their descendants look very different any culture in our world but would probably still be vaguely Chinese or Korean in appearance, sometimes with brown hair), their language becomes the language of Northern and Central China. They continue to recognize Chinese thinkers like Confucious or Lao Tzu [Actually, since Confucianism does not undergo state-sponsored repression, the ideology grows and develops in different ways but never comes as close to a religion as it did in our world] and fully embrace ancestor worship, but remnants of their chariot-driving twin deities (thunder and lightning) persist. The Horse and Cow take on a prominence not found in our China, leading to China's rather unique taste for pork not forming and rather more dairy products in locals' diets. Both the Selang-Arsi and the Han people they intermix with continue to be clan-oriented in the absence of any large-scale state building projects. As the Selang-Arsi spread north, they assimilate Machus and the peoples of the Korean peninsula.
A second group set of peoples migrates into the North China Plain in period from 200 A.D. to 600 A.D. These are North Iranic Peoples- relatives of the Scythians (whose closest modern-day equivalents in our world would be the Ossetians), populating a region streatching from the Dneiper to the Altai mountains. With a very different Middle East and a partially Hellenized Bactria invading Sogdiania in Central Asia, much of the medieval horse archer steppe horde migrations has gone rather more uniformly west-to-east in this world. Though numbering in hundreds of different tribes (and absoring non-Iranic steppe peoples such as the Turks and Mongols) these people unify on the steppes (referred to by residents of the Middle Lands as the people of 'Kang,' originally a term connotating just Sogdiana). When this land is conquered by the Greek-speaking Bactrians, there is just enough push to bring about a second great migration into the Middle Lands. The Kang leave an even smaller genetic inprint on the Middle Lands, but in the central part of the country (still contested between the Selang-Arsi and the Han) one of the Iranic languages becomes the common tongue of the masses.
The Middle Lands then, are not an Empire. But there is a common civilization of sorts, one which solidifies in the next thousand years. Following Confucius and Lao Tzi, new generations of philosophers write treatistes on harmony, duty, and nature (legalism, meritocratic tests for officials, and bureacracy all remain noticeably absent). The earliest forms of Classical Chinese, though not a spoken language for long, continue to be the primary written language of all the local peoples. Buddhism, Hinduism, Hellenization, and any additional foreign influences, are resisted as the Selang-Arsi, Kang, and Mian (the large Han state that eventually forms in the South) close ranks as the true 'natives' of the Middle Lands.
By 1975, history has moved forward, though rather differently. The Middle Lands remain technologically in the Iron Age, equivalent in the most advanced parts (say, on the *Korean Peninsula) to OTL Rome in the 3rd Century A.D. (and maybe with worse aquaducts and roads), and elsewhere roughly as technologically advanced as ancient Persia. The printing press, paper, and the compass exist, but have only been invented in the Greek Middle East, and this world has nothing along the lines of gunpowder, steel, or windmills. The Selang Arsi and Mian both do have improved wooden-navies scattered across the East China Sea. The Selang Arsi attempted to conquer the even more primitive land of Yamato (ruled by its own God-King), starting in 1555, but after four centuries of conflict and slow-rising up of the natives, the Selang-Arsi have (mostly) been kicked off the islands by angry locals.
In 1975, U.S.-made helicopters which have been transported from another dimension, land down in a small Selang-Arsi fort town at the sight of what in our world would be Beijing. The strange humans exiting them are hailed as gods by some, but the local king quickly realizes that they are at worst potential conquerors and at best potential trade partners...