In the previous two episodes (episode one and episode two) I have mainly covered Tang’s military and political advancement in the central Asia and the consequential Tang’s governance in the region. In this episode I will specifically focus on Tang’s foreign relations with the strong power that Tang had to deal with in Central Asia.
Central Asia was never an easy place to maintain stable power until the Tsar Russia came in kick all the nomadic tribes’ off their horses with rifles. The place is literally accessible from every corner of the old continent (comparably Chinese access to central Asia being the narrowest through only Hexi corridor and Gobi desert). During Tang’s control over central Asia in the 7th and mid-8th century, China had direct access to almost every great civilization in the world. At that time major foreign power that came into direct contact with Tang in the central Asia were Tufan from the Tibetan Plateau southeast of central Asia; Indian kingdoms southeast of central Asia, Sassanid Empire of Persia southwest of central Asia (later the Arab Caliphate), and even Byzantine Empire from the far west of central Asia.
In Episode 2, I have already mentioned that Tang adopted a semi-military administrative system in central Asia, while at the same time maintaining a number of tributary nomadic tribes and oasis city states to be in charge of themselves. Tang garrisoned its central Asian troops in only several main cities, and made those cities the administrative locations for solving tribal disputes and taxing merchants on the silk road. Tang’s direct military force was always kept in the Transoxiana region (河中 the fertile valley in between Amu Darya River and Syr Darya River) in central Asia. Most of the Turkic tribes in vast central Asia were under their own autonomy and all submit to Tang as the leader of all tribes. All Turkics in central Asia were fighting under the name of Tang Empire at the time; and Tang’s picked veteran Anxi army always made sure that those who disobey Tang’s order would be ruthless punished and other power influence would not be able to challenge Tang’s hegemony in the region. In this article I will emphasize on Tang’s relations with the two main power during its hegemony period in Central Asia (630AD – 755AD), namely Persians and the Arabs, with a brief scanning on Tibetans.
Sino-Persian alliance (Sassanid Perisa)
Even before Tang got in touch with Sassanid Persia (波斯 in Chinese), the last pre-Islamic Persian dynasty, the old Zoroastrian empire, has already been on the downhill track out of tiresome wars with the Turks and Byzantine and endless domestic political chaos (they even had a proto-commie named Mazdak trying to start off a revolution within the empire). When Tang first had direct contact with its Persian counterpart, presumably no later than 630AD when Western Gokturks submitted and recognized Tang Emperor Taizong as the Celestial Khagan, both courts were aware of the need for mutual assistance in maintaining the order in Central Asia and formed extensive military alliance against the common foes in the region, the Turkics and possibly the Hephthalites. The tight connection between the two courts were also strengthened by the rapid expansion of economic ties between the two countries along the newly re-opened silk road. Chinese silk, tea, and porcelain were highly valued by the nobles in Ctesiphon and Chang’an started to hold a considerable size of Persian community composed of Persian traders and travelers. Nestorian churches and Zoroastrian temples were allowed to be built in Chang’an. In fact people were so amazed at the exotic travelers at the time that the whole Chang’an started a Persian fashion fad. Women scrambled to dress like Persians and men flocked to brothels for the Persian dancer. Lots of folklore of the Persians at that time even survived up to nowadays in China.
There was not even a single military conflicts recorded between the two empires in Central Asia. Both courts had always considered each other dependable military ally and close economic partner. Of course this alliance was not simply because of the economic trade and the friendliness of both courts. At that time, Persia was swamped withstanding the ferocious Arab invasion from the West and hoped to secure its eastern borders, which was often harassed by the Turkics from the Northeast. The alliance with Tang, an emerging power which could have the potential to tame the Turkics in its eastern border, was deemed important for the Persians. The Chinese, on the other side of the silk road, was also not quite relaxed in maintaining its dominion in the central Asia due to frequent Turkic rebellions. Realizing the long geographical distance between Persia and China, Tang court would also be in favor of an alliance with the remote occidental empire so that the Anxi troops could concentrate on crushing Turkic rebels only. Coincidentally, when the cruel Arab horsemen galloped across the whole Iranian lowland and highland in 651AD, the Chinese managed to smash the last resisting force of the Western Turkic Khanate only 8 years later (see episode 1). Would there be an outbreak of the Sino-Persian conflict after Tang’s hegemony being established, if Persia had also manged to deter the Arab nomads like the Byzantine or the Carolingian Francia? Probably, but we would never know anyway. Nobody expected that the Arabs would sweep off the Persians in a blizzard manner. The Sassanid court must be extremely frightened at the time. The last emperor, Yazdgerd III, sent his son, Peroz III to the Tang-controlled Central Asia (possibly arrived in Suyab), in the hope of getting military assistance from the Chinese against Arab invasion at the last moment (He arrived in Chang’an in 661AD). Tang court deemed the call for assistance as a perfect chance to expand its Anxi Protectorate to the land of Persia, therefore gladly accepted the request and sent a general to escort the last Persian prince to restore the Sassinid order. For some unknown reasons the troops didn’t advance further westward from Suyab and the Persian prince stayed there for over 20 years. I reckon the Chinese generals in Suyab must hesitate with direct large scale confrontation with the Arabs at the time and be busy with the increasing Tibetan harassment from the Southeast. Either way, Tang army never escorted Persian prince to Persia and Arabs did not continue their further expansion eastward either. The Persian royal blood from Peroz III survived in Tang China and was granted as nobility in southern city Guangzhou and gradually assimilated into the local population.
When Persians surrendered to the Arabs (大食 in Classic Chinese) in 651AD, they also told them about the legends of another group of fierce horse fighters (the Turkics) from the northeast. Al-Ahnaf Ibn Qays, the conqueror of Persia for the Umayyad Caliphate, decided to cease the campaign further eastward and maintained a status-quo with the Turkic nomads in Central Asia (their attempt to expand eastwards was met with fierce resistance of the Turgesh tribes 突厥施). Likewise, the head of all Turkic nomads at the time, the Tang emperor did not plan to expand further westward either, probably shocked by the speedy conquest of Persia at the time.
Interestingly, way before Arab horsemen knocked at the doorsteps of Tang’s Central Asian protectorate, we are talking about the time when Mohammed started to preach Islam in late 6th century AD, the Islamic prophet sent various envoys to different leaders in the world in the hope of converting them to Islam. China was one of those destinations. The envoy of Mohammed, Saad ibn Abī Waqqās, arrived in China twice in 616AD and 651AD. Of course Tang royal family did not convert to Islam in the end, nor did the Chinese. But the practice of Islam among Arab merchants in southern seaport like Guangzhou was largely tolerant by the imperial court. The Arabs were at that time at the dawn of a massive wave of expansion in all dimensions. It didn’t take long for the them to finally meet the Chinese in Central Asia. Simultaneously, by the time Arabs engulfed Persia, Tang was also on the rise of military supremacy in the adjacent region. With the subordination of local fierce Turkic fighters and the presence of powerful Anxi troops, Arabs chose not to advance eastwards immediately after taking over Persia. Instead, Uthman ibn Affan, the third Caliph of the Umayyad Caliphate, sent an embassy to Chang’an right after the capture of Persia around 650sAD. The friendly gesture of the new Arab lords in Persia probably was another reason why the imperial court in Chang’an did not really enforce the restoration of the Persian court at the same time. This de facto peace between the two emerging power in the mid 7th century in Central Asia enabled both parties to have enough energy to deal with other hassles (Arabs were stuck in Anatolia and later started internal political conflicts; Chinese were busy with the Tibetans after 670AD and stabilized the dominion in Central Asia by 692AD).
After decades of peace, the friction between the two mighty power finally broke out in 715AD. In that year, Arabs collaborated with the Tibetans to support a Sogdian named Aliaoda (阿了達) as the new king of Ferghana (拔汗那, around nowadays Fergana, Uzbekistan) to revolt against Tang’s suzerainty. The old king rushed to Anxi garrisons for Tang’s help. Immediately Tang mobilized a rapid campaign with various Turkic tributaries and defeated the Arab-Tibetan alliance and restored the old king in Ferghana. This was the first attempt for the Arabs to challenge Tang’s hegemony in Central Asia. The Arabs would now seek any opportunities to advance to China, a fertile rich land that has been longed by Arab generals for decades. Soon after the defeat, in 717AD Arabs organized another wave of attack. This time they even lured the Turgesh tribes, who once fiercely resisted Arab influence and allied with Tang, to fight against the Tang army together with Arabs and Tibetans. Their aim was to take over the four important Tang’s Anixi garrisons in Central Asia and eliminate Tang’s military projection in the region. However, they underestimated the prowess of Tang’s fearsome Anxi troops and were once again defeated very quickly. Turgesh tribes after the war immediately submitted with Tang and besieged the Arabs in Northern Transoxiana region in 718AD, who already cleared Tang’s army there and prepared for a long match directly into China proper (Tang rewarded Turgesh with the city of Suyab in 719AD for their loyalty). Tang soon recovered the Northern Transoxiana and Arabs had to pay a large amount of gold as ransom for the return of their defeating army. Arabs were clearly frustrated with the warfare with Tang in Central Asia after series of defeat. By the time of 723AD, they changed the general for the Chinese campaign and started another wave of aggression against Ferghana (this time alone). Tang court did not use a single rider in the Anxi garrisons to counterattack Arab’s invasion. Instead, the Emperor Xuanzong issued an imperial edict to order the Turgesh riders, who were once again subordinated to Tang, to smash Arab’s attack in Ferghana. Being the nemesis of the Arabs, Turgesh easily crush Arab troops and freed Ferghana once again from Arab invasion. One year later, Arabs reorganized another large scale campaign on Ferghana, with the help of their new tributary Turkic and Sogdian tribes. They managed to besieged the Capitol city of Ferghana for days. In the end, Turgesh fighters, delegated by their Tang lord, arrived in time and nearly wiped out the whole Arab army. After this battle, those Turkic and Sogdian tribes, including the Sogdian tribes Shiguo (石國) and Kangguo (康國) who played important roles in the demise of Tang’s glory decades later, immediately back-stabbed the Arabs and re-embraced Tang’s suzerainty. By 724AD, Arabs suffered severe casualty and lost the control over the few remaining central Asian tribes in a series of defeat. On the other side, Turgesh were dispatched as Tang’s proxy in the defense of areas west of Pamirs against possible Arab aggression in the future (Anxi army withdrew back to the Pamirs). This status-quo maintained for nearly 20 years, until the famous Battle of Talas broke out in 751AD.
In 751AD, According to Chinese record, Sogdian tribe Shiguo failed to pay tribute to the Tang court in proper etiquette (Sogdians probably were plotting another revolt against Tang at the time). The court ordered the then Anxi Protectorate General, Gao Xianzhi (高仙芝), to match towards Shiguo (around today’s Tashkent, Uzbekistan) with Anxi troops to “exert” the imperial might to the ill-mannered barbarians. This was when the drama started. The king of Shiguo immediately pleaded to surrender when Gao Xianzhi showed up in front of the capital with numerous iron riders. Gao Xianzhi first appeared to accept the surrender. But as soon as Sogdians dropped the weapons he immediately ordered the riders to start a horrible pillage and massacre in the capital. Somehow the prince of Shiguo was lucky enough to escape the town just in time and rushed to the Arabs for assistance. When Tang heard the news that Shiguo is going to get Arabs on the back again soon, Gao Xianzhi decided to lead his 10,000 Tang’s Anxi army, along with 20,000 Karluk (葛邏祿, a Turkic tribe around Ferghana) mercenaries to go deep into Arab’s dominion and attack the Arabs by surprise. It was indeed a big surprise, but to the surprise of Gao Xianzhi, the Karluk had already made a deal with the Arabs to back-stab Tang right on the battlefield. It was a set-up all along. Karluk wanted to use the Arabs to get rid of the Chinese, and the Arabs would love to ally with anyone who would go against Tang at the time in order to fully conquer central Asia. The Anxi army was all of sudden under tremendous pressure from both the outnumbering Arab troops in the front (aprox 200,000) and the back-stabbing Turkics in the back (20,000). However, Anxi army still managed to magically retreat with a small remaining troop back to garrisons, and Arabs still suffered a heavy loss despite a decisive victory. This battle was very significant in history. The Arabs gave up their Chinese campaign as they realized Anxi troops were too tough to swallow despite their victory. Some of Chinese solider were captured and helped the Arabs set up the first paper mill in Samarkand right after this battle. Papermaking was then gradually spread all over the Arab world and finally to Europe. The Chinese, despite the defeat, didn’t lose their military supremacy in Central Asia after this battle. Anxi army still managed to repress the rebellions from various tributaries west of Pamirs right after the battle. Tang’s hegemony continued until 755AD when the rebellion took place within the China proper (Anxi army were order to return to China proper to repress the rebellion). Karluk was the ultimate winner. They gained independence from Tang, and gained permission from the Arabs to establish their polity in the region. As an exchange, the Turkics agreed to convert to Islam. For the first time Islam infiltrated among the Turkics in the Central Asia, once a land of Buddhism, with the help of this Arab-Turkic alliance.
Even though Tang experienced a drastic downfall after 755AD’s internal rebellion, the Arabs had never advanced further to Tang’s central Asian garrisons. The Chinese fortifications withstood numerous waves of aggression from the Tibetans and the New Turkic power, the Uighur, even 50 years later after the withdrawal of major force back into China proper. Tibetans and Uighur became the new lords of central Asians instead of the Arabs. Meanwhile, Islam was gradually spreading with the resurgence of the Turkic nomads in the region.
Tibetans in the first era of Tang’s hegemony (up to 670AD) did not cause a single problem to the Chinese because of the successful political marriage arranged by Taizong in 641AD. However, the friendly attitude changed completely after the death of Songtsän Gampo. The new Tufan king had longed for the rich trade route of the silk road and started the first attack in 670AD. They had made some temporary progress in capturing some of the Chinese garrisons in the region, but were soon expelled away. The Anxi troops finally thwarted Tufan’s Central Asian campaign in 692AD when General Wang Xiaojie (王孝傑) fatally crushed Tibetan troops around the four Anxi Garrisons. Since then Tibetans were no longer able to pose any significant threat against Tang’s reign over central Asia, even if they allied with the Arabs. The opportunity for Tufan came finally when the main Anxi army returned to China to clear the An Lushan Rebellion in 755AD. Tibetans from the south along with the emerging Uighur from the north gradually nibbled Tang’s western protectorate in the following 50 years.
History is a stage full of drama. After Tang’s iron Anxi army was sweeping across the steppe and deterring the Arabs for decades, a domestic revolt led by a Sogdian general drastically dragged Tang down from the top of power in central Asia to completely being defenseless in only 50 years. Ironically, Tibetans soon followed Tang’s path and never recovered even since its internal conflict in the 800s AD. The land of steppe once again fell into the hands of Turkic nomads. The downfall of the once-invincible Tang Empire in the central Asia will be further discussed in the next episode (also the last one): The Demise of the Empire.