When the Tibetans and Uyghurs overran China

The worrying developments in Xinjiang seem to have finally caught some of the world's attention, although it is far from becoming the cause célèbre that Tibet was in years past. Modern China's relationship with its minorities in these two regions remains fraught, and any compromise seems unlikely. It is interesting to look back at a time when the balance of power was reversed, and the Tibetans and Uyghurs made up formidable fighting forces that almost overran China.

Back in the middle of the eight century CE, China was ruled by the fabled Tang dynasty, now remembered for presiding over a golden era of prosperity, openness to the world and even women's rights (China's only ever female ruler, Wu Zetian, took power in this period). The capital Chang'an was the world's largest city with two million people, and the Tang dynasty was the world's largest empire. The cosmopolitan capital included quite a few non-Chinese among its inhabitants, probably in a higher proportion than you would find in any Chinese city today. Nowadays Chang'an is known as Xi'an, a city that sits in the middle of an arid, impoverished backwater, but in those days China's North-West was the empire's flourishing centre, while Southern China remained on the perifery.

To its North and West, Tang China was flanked by two mighty empires: the Tibetan empire and the Uyghur Khaganate. We are used to hearing about these two peoples as beleaguered minorities in modern China, unable to even beginning to compete with the Han in terms of numbers, resources and power. The balance of power was however quite different at the time.

The Tibetan empire came into being in the 7th century CE, when a specific clan gained control of central Tibet and based their capital in Lhasa, which has remained Tibet's main urban centre ever since. Even though Tibet has always had a harsh and unforgiving natural environment, over the next two centuries its rulers created a powerful state and expanded over a much larger area than the Tibetan plateau, gaining control over much of what is now Xinjiang, Yunnan, Kashmir, Nepal and even Bengal. The Tibetans at this stage were not yet Buddhists, although it at this time that Buddhism appeared in the Tibetan plateau. Buddhism in China, however, was enjoying the peak of its popularity.

A statue of Songtsen Gampo, unifier of Tibet and founder of the Tibetan empire, in one of the ancient meditation caves of Yerpa, outside of Lhasa

The Uyghur Khaganate, on the other hand, was a tribal confederation of Turkic-speaking peoples that existed between the eight and the ninth centuries CE. It spanned a huge area covering modern Mongolia, the north of modern Xinjiang, and a big chunk of Russian Siberia and Northeastern China, reaching all the way to the Pacific. Its capital was at Ordu Baliq, now in Mongolia. Its ruler was the khagan, which in Turkish and Mongolian languages is a title of imperial rank. Given that Turkic languages, which now spread all the way from Xinjiang to Turkey, actually originated in what is now Mongolia, it is not surprising that the khaganate was based there.

It should be recognized that although this kingdom was known by the term "Uyghur", its relationship with the people currently known as Uyghurs is not straightforward. The term "Uyghur" was rediscovered by the Soviets in the early twentieth century and used to define all of the settled Muslims of Xinjiang, which is what it refers to in China today. Although modern Uyghurs are partly descended from the people who made up this empire, and they also speak a Turkic language, they are probably also descend from other groups. In fact, it is likely that the Uyghurs of the time had much more East Asian facial features than the current Uyghurs do. At the time the Uyghurs followed Shamanistic beliefs, although the official religion of their state later became Manichaeism.

Over the first part of the eight century, the Tibetan empire and Tang China were constantly fighting each other for territory. In 755, a devastating rebellion against the Tang dynasty was begun by a general named An Lushan. As was often the case with Chinese generals in these cosmopolitan times, An Lushan himself was not a Chinese. His ethnic origins are uncertain, but his adoptive parents were Sogdian (an Iranian-speaking civilization in Central Asia) and Turkic. He reportedly spoke six languages on top of Chinese.

An Lushan, the "barbarian" general who almost brought down the Tang dynasty

As Chinese historical records would have it, the events that led to this rebellion were put in motion by the Chinese emperor at the time, Xuanzong, who had reigned since 713 CE. Although initially a shrewd and competent emperor, by about 736 he had become tired with affairs of state, and turned his attention to artistic pursuits and his favourite courtesan, Yang Guifei (one of China's traditional "four great beauties"). He consequently left all affairs of state in the hands of his chief minister Li Linfu, remembered as a villanous figure who purged all real or imagined opponents and became a de-facto dictator. One of his moves was to nominate only non-Chinese to the powerful posts of military governors of the different regions of China. His reasoning was that lacking ties to the court, they would not enable any rivals to gain power on the basis of military success. This is not strange when you consider that at the time, a big chunk of the Chinese army consisted of non-Chinese mercenaries. An Lushan was thus nominated military governor of the North-East (corresponding broadly to what is now Hebei and Shandong), and amassed lots of power.

When Li Linfu died in 752, Xuanzong replaced him with Yang Guozhong, the second cousin of Yang Guifei, his beloved courtesan. Yang Guozhong intended to eliminate An Lushan, who consequently rebelled. An Lushan's rebellion was a blow from which the Tang dynasty never really recovered. It continued for years and caused the death of millions by starvation and disease. In the broader scheme of things, it probably put an end to the aristocratic system that still dominated China, and brought about the social and economic changes that would create the bureaucratic, examination-based system of later dynasties.

After the rebels took the capital, the emperor's court was forced to flee to Chengdu. Xuanzong's angry troops rebelled, killed Yang Guozhong, and forced the emperor to have Yang Guifei strangled. Even Confucian scholars would later disagree on whether she was the author of her own downfall, or a convenient female scapegoat. An Lushan was killed by his own son in 756, but the rebellion went ahead. In order to suppress the rebels, the Tang dynasty sought the assistance of the Uyghurs. The Uyghurs contributed 4000 cavalrymen to the imperial army, which was then able to retake the capital from the rebels.

In 762 the Uyghurs also assisted with the recapture of Luoyang, now an unremarkable provincial city, but then a second capital of sorts, with a population second only to Chang'an itself. The Uyghurs only helped on condition that they could loot the city. In the sacking of Luoyang, in which the Uyghurs were joined by Chinese troops, tens of thousands of civilians were killed and the city burned to the ground. The Uyghurs' behaviour was certainly not exemplary: when civilians fled to Buddhist temples looking for protection, the Uyghurs burnt those down as well. Ironically it was during this adventure that the Uyghur khagan encountered Manichean priests and decided to adopt this faith for his kingdom. Manicheaism is based on the idea of a constant struggle between good and evil.

The rebellion was finally crushed in 763, but in the meantime the Tibetan empire had occupied more and more of Northwestern China's grasslands, taking advantage of Chinese weakness. In 763 the Tibetans actually occupied China's capital, the great Chang'an, for fifteen days, attempting to install a puppet emperor. Although they were quickly kicked out of the capital, they continued to rule over areas previously under Tang rule where many Chinese resided.

The next year yet another important Tang general, Pugu Huaien, decided to rebel after fearing that he would be accused of treason. He was also of Turkic descent, and if he wasn't a Uyghur then he was closely related to them. In fact he had been instrumental in setting up China's alliance with the Uyghurs. When Pugu Huaien rebelled, the Uyghurs and the Tibetans immediately joined him. They were ready to launch a joint attack on the Chinese capital when he died in September 765. The Uyghurs then switched sides again, and helped the Chinese finally push back the Tibetans.

Over the next decades the Uyghurs exploited the Tang's weakness and its need to keep them as allies by extracting rights of extra-territoriality for the Uyghurs and Sogdians who lived in Chang'an and other Chinese cities, so that they would not be subjected to local law. Their immunity from Chinese law, and their money-lending activities, created resentment and anti-foreign feelings amongst the ordinary Chinese which may have laid the basis for the massacres of foreign residents a century later.

A mural commemorating the victory of a successful rebellion against the Tibetan Empire in 848, led by the Chinese residents of what is now Gansu province

Within a hundred years of the events described above, both the Tibetan empire and the Uyghur Khaganate would be history. The Tibetan empire collapsed in the 840s, after a civil war fragmented it and led to the rule of regional warlords over the Tibetan plateau. Tibet would only be unified again under the Mongols, four centuries later. The Uyghur Khaganate collapsed around the same time, after a particularly severe winter in an already cold land killed much of the livestock which its economy depended on, after which the Kyrgyz invaded and sacked the capital. The Uyghurs migrated south and west, became Buddhists and then finally Muslims, mixing with others to constitute the Uyghurs we know today.

It is probable that China, with its much larger population, fertile land and sophisticated bureaucracy was always going to last longer than any Tibetan or Uyghur polity could. Nowadays China is one of the major powers of the world, within whose borders the impoverished and marginalised descendants of the Tibetan and Uyghur of the time are fighting a losing struggle against an assimilation which at least in the case of the Uyghurs has become worryingly forceful. The fact that they once outfought the whole of China and almost led a joint assault on its capital is not well-remembered.

But it is interesting to look back at a time when Tibet was a military threat and the Uyghurs were in a position to blackmail the empire. It is also fascinating to think that China's destiny could be decided by rebel generals who spoke Turkic languages as their mother tongue. Unlike China's current ethnic minorities, non-Han living in China in those days were not constantly being told they were Chinese. From what we can see, their foreign status seems to have been recognized both by themselves and others. An Lushan used to joke with the emperor about how as a barbarian he could not understand Chinese court etiquette. At the same time, these "foreigners" were allowed to amass power and become real players at the national level in a way that members of minorities nowadays would find very hard to do, at least if they are distinguishable from the Han by speech or custom.