Raid on Yanmen (621)

Ilig Khan had become khan of the eastern Göktürks the year before. In the fourth month of 621 he attacked the Tang frontier commandery of Yanmen with more than ten thousand horse.^[1] With him came Yuan Junzhang, a rebel who held Mayi, with six thousand men.^[1] Li Da’en, the Tang prince of Dingxiang, drove them off.^[2] The Zizhi tongjian enters the attack under the day jihai of the fourth month.^[3] At that time both courts were holding each other’s envoys. According to the Zizhi tongjian, the envoys were released only in the spring of 622.^[4]

Background

Ilig had come to the throne in 620, and from his father and his brothers he inherited a strong army and the ambition to overawe China.^[1] The central plain had only just been settled, and the Tang emperor Gaozu indulged Ilig. He gave him gifts beyond counting.^[1] Ilig’s letters grew insolent, and his demands had no end.^[1]

His wife, the Sui princess Yicheng, had a kinsman among the Göktürks, Yang Shanjing.^[5] The Xin Tang Shu makes him her younger brother, while the Zizhi tongjian makes him her cousin.^[5] He and Wang Wensu, an envoy of the rebel Wang Shichong, urged Ilig to repay the house of Sui.^[5] They argued that Ilig’s father Yami had been restored to his throne by the Sui emperor Wen, and that the new emperor of the Tang was not of Wen’s line.^[6] Ilig agreed. The Xin Tang Shu says that from then on he raided every year.^[6] In the third month of 621 the Göktürks raided Fenyin and Shizhou.^[3]

The envoys

Before the attack the Tang had sent envoys to the Göktürks. Among them were the duke of Hanyang, the chief of the Court of Imperial Sacrifices Zheng Yuanshu, and Changsun Shunde, a general of the Left Guard.^[2] Ilig held them all. The Tang in turn held several of his envoys, one after another.^[1]

The Zizhi tongjian tells how it came about.^[3] Zheng Yuanshu had gone to Chula Khan, Ilig’s brother and predecessor, to warn him, and Chula would not listen.^[3] Chula fell ill and died soon after. His people suspected Zheng Yuanshu of poisoning him and kept him.^[3] The duke of Hanyang then brought gold and silk to Ilig. Ilig wanted him to bow, and he refused, so he was kept as well.^[3] Changsun Shunde was also held back. In his anger the emperor then held the Göktürk envoys.^[3]

One modern account reverses the order.^[7] In it the newly crowned Gaozu had all the envoys and guests from the Göktürk realm arrested in protest. Ilig answered by ordering the arrest of the Chinese in Ötüken.^[7]

The attack and the raids of the autumn

The Chinese histories give the attack on Yanmen a single sentence and end it with Li Da’en’s victory.^[2] The Zizhi tongjian adds that the Göktürks raided Bingzhou nine days later.^[3] One modern account tells the campaign the other way round. In it the Göktürks brought the commandery under their control. They then beat the Tang armies decisively in five battles.^[7]

The Xin Tang Shu goes on to say that from Yanmen the Göktürks raided Daizhou and beat the Tang commander Wang Xiaoji.^[6] They plundered Hedong, fell on Yuanzhou and broke through the frontier of Yanzhou. The Tang generals who fought them took no prisoners.^[6] The Zizhi tongjian dates the defeat of Wang Xiaoji to the day guimao of the eighth month, when his whole army was lost.^[3] The Göktürks went on to besiege Guo county.^[3] Li Da’en had few men, but he held his town. The Göktürks did not dare to press him and left after more than a month.^[3] In the ninth month they raided Bingzhou and Yuanzhou.^[3]

The modern account dates a thrust into Taiyuan to August 621.^[7] Gaozu met it with an offer of tribute and the hand of a Chinese princess.^[7] Ilig accepted, withdrew and freed the Chinese held in Ötüken. Gaozu did the same in Chang’an.^[7]

The fish glue

The Jiu Tang Shu says that the defeat at Yanmen frightened Ilig.^[1] He sent Changsun Shunde home and asked for peace.^[1] With the request went several dozen jin of fish glue. Ilig wished that the two states should hold together like the glue.^[1] Gaozu was pleased. He released the Göktürk envoys, among them the tegin Rehan and Ashide, and sent them home with gold and silk.^[1]

The Xin Tang Shu places the release in the following year.^[6] It calls Ilig’s words about the glue a pretence. In its account the emperor sent the envoys back although he did not believe them.^[6] The Zizhi tongjian sets the exchange in the third month of 622 and gives it a different cause.^[8] The emperor sent envoys to bribe Ilig and promised him a marriage. Ilig then sent the duke of Hanyang, Zheng Yuanshu and Changsun Shunde home.^[8] On the day gengzi he sent envoys to restore good relations, and the emperor released the tegin Rehan and Ashina De.^[8] Where the Jiu Tang Shu has Ashide, the Zizhi tongjian has Ashina De.^[4]

The peace did not last the spring. In the same entry the Zizhi tongjian has Ilig besiege the Tang commander Liu Shirang at Yanmen for more than a month. The rebels Gao Kaidao and Yuan Junzhang were with him.^[8] The campaign of 622 followed.^[1]