People familiar with the history of the Sui and Tang dynasties will know that during the Sui and Tang dynasties, there was once a strong nation active in the north, which had been enemies of the Central Plains for many years and threatened the rule of the Central Plains Dynasty many times, which was the Turkic Khaganate.
The Turkic Khaganate rose in the middle of the sixth century, and during the confrontation between Northern Qi and Northern Zhou, the Turkic Khaganate defeated Rouran, and subsequently, it became the most powerful nation in northern Mobei.
The surname of the Turkic Khanate was Ashina, which is also mentioned in the history books, but it was such a renamed khanate that greatly influenced the Central Plains Dynasty. In the future, when it is destroyed, three generations of its royal family will bow down for the Tang Empire and become an auxiliary helper of the Tang Empire.
It is hard to imagine that a khanate that had been enemies of the Central Plains for generations eventually became a vassal state of the Tang Empire, which showed the assimilation of the Central Plains Dynasty.
At the beginning of the Sui Dynasty, the Turkic Khaganate was divided, and the Eastern Turkic forces dominated by Sha Baoliu Khan took advantage of the early establishment of the Sui Dynasty to repeatedly send troops south to harass the frontiers, and in order to eliminate the hidden dangers of the Turks, Emperor Wen of Sui followed the strategy of Sun Sheng to conquer the Turks in the north, and after a series of blows, the Turkic Khaganate was finally defeated. Sha baoliu Khan recognized the strength of the Central Plains Dynasty and took the initiative to surrender to the Sui Dynasty.
The dependence of Sha baoli Khan was temporary, and it was only because of the strength of the Sui Dynasty that it had to defect to the Sui Dynasty. In the future, when the time is ripe, the Turks will still rise. During the reign of the Eastern Turk Qimin Khan, the Sui Dynasty was close to the Turks.
Due to the previous great war between the Central Plains and the Eastern Turks, it eventually led to the decline of the Eastern Turks' power. It was precisely because of this that the Western Turks rose rapidly.
Although the Eastern and Western Turks belonged to the same people, they all had the desire to expand their territory. Thus, in the middle of the kaihuang, the Western Turks continued to invade the Eastern Turks. In order to balance the forces of the two sides, Emperor Wen of Sui sent envoys to persuade the two sides many times. Under the threat of the Sui Empire, the Eastern and Western Turks finally temporarily restored peace.
The subordination of the Turks was based on the strength of the Central Plains Dynasty, and once the Central Plains Empire was in civil strife, it still had to raise troops to invade the south. When the peasant revolt broke out at the end of the Sui Dynasty, the Turkic Shibi Khan took the opportunity to lead an army south to attack Yanmen, when the Sui Emperor was touring the north, so unfortunately he was besieged by the Turks for a long time in Yan County.
At a critical moment, the Sui Emperor adopted the practice of passing on the edict of driftwood, and the various reinforcements of the Sui Dynasty arrived one after another. Seeing that the Yanmen Gate could not be breached for a while, and seeing that the Sui Dynasty reinforcements had arrived, he had to lead the whole army back to the Turks.
If the Siege of Yanmen was the beginning of a formal war between the Turkic Khaganate and the Central Plains Dynasty, then the Battle of Yinshan was the climax of the war. When Tang Gaozu Li Yuan raised an army in Jinyang, the Turks had raised troops to the south, and at that time Li Yuan was in the stage of entrepreneurship, and his power was still very weak, out of consideration for the safety of Jinyang, Li Yuan had to submit to the Turks.
After Emperor Taizong of Tang succeeded to the throne, the tang dynasty's national strength increased, and Emperor Taizong remembered the shame of the bridge, so he launched a war against the Turks with Zhenguan in the early stages. Especially in the Battle of Yinshan, the Tang army was even more ambitious for the Central Plains Empire. The Eastern Turk Jieli Khan was captured, and the Tang Dynasty finally conquered mobei.
After the fall of the Eastern Turks, the power of the Turkic royal clans was greatly weakened, and the Western Turks took the opportunity to rise. However, due to the internal differences in the Western Turks, there were two forces mainly based on Ashina Buzhen and Ashina Mud, Ashina Buzhen and Ashina Mud, who were both brothers and khans, and Ashina Mud was the first to be excluded and had to surrender to the Tang Dynasty, and Ashina Buzhen also switched to the Tang Dynasty because of the failure of the Khan.
It was from this time that the royal families of the Eastern and Western Turks became vassals of the Tang Empire, and some of them even became the main generals of the Tang Dynasty army.
In 657, the Western Turkic Ashina Helu rebelled and invaded the Western Regions from time to time, and Li Zhi, Emperor Gaozong of Tang, faced with this situation, led the Tang army to conquer the Turks with the general Su Dingfang as his commander. After months of conquest, Ashina helu was finally pacified.
Later, in order to better control the Western Turks, Emperor Gaozong re-established Ashina Buzhen and Ashina Ni as khans.
Since the Turkic khans all needed the support of the Tang Dynasty, there would naturally be a number of Turkic generals in the Tang army, and the famous Turkic generals Qifu Heli and Ashina Sima were representatives.
Both Qifu Heli and Ashinasimo were originally subordinates of the Turkic Jieli Khan, and only after the fall of the Eastern Turks did they switch to the Tang Dynasty. In order to better control the north, Emperor Taizong used Ashina Sima to guard the northern frontier for a long time, so Ashina Sima became a major general under the jurisdiction of the Tang Empire.
During the reigns of Emperor Gaozong and Emperor Zetian, the Turkic royal family continued to serve the Tang Dynasty, and Ashina Yuanqing, the son of Ashina, served as the governor of Kunling in the Tang Dynasty.
In the middle of Emperor Xuanzong of Tang, Ashina Yuanqing's son Ashina Xian accompanied Zhang Xiaosong on his western expedition to Dawan, which shows that since Emperor Taizong of Tang, the Turkic royal family has become a vassal of the Tang Empire for three generations, and they have made important contributions to the strength of the Tang Empire.
[References: Sui Shu Ji Xia, Old Book of Tang, New Book of Tang, Zizhi Tongjian]