Göktürk Aid to Li Yuan (617)

In 617 Li Yuan, the duke of Tang, rose against the Sui at Taiyuan. He sent his officer Liu Wenjing to Shibi Khan to ask for help.^[1] Shibi sent the tegin Kang Shaoli with a thousand horses to meet him in the Jiang commandery. Shibi also sent two thousand riders, who helped Li Yuan take the capital.^[1] When Li Yuan took the throne as the first emperor of the Tang, his gifts to Shibi could not be counted.^[1] Modern accounts hold that the alliance of 617 put a Göktürk khan behind the founding of the Tang.^[2]

Li Yuan’s letter

The Zizhi tongjian tells of the negotiations under the sixth month of 617.^[3] Liu Wenjing advised Li Yuan to ally with the Göktürks and use their soldiers and horses to strengthen his army.^[3] Li Yuan wrote to Shibi in his own hand, in humble words and with rich gifts.^[3] He wrote that he wished to raise a righteous army and bring the emperor back. He also wished to renew the peace and marriage alliance with the Göktürks, as in the Kaihuang years.^[3] If the khan would march south with him, he asked only that the people be spared. If the khan wanted only peace and the treasure that came with it, that was his choice too.^[3]

Shibi read the letter. He told his ministers that he knew the Sui emperor.^[3] If he were brought back, he would surely destroy the duke of Tang and then attack the Göktürks.^[3] “If the duke of Tang makes himself Son of Heaven, I will not shun the summer heat; I will help him with soldiers and horses.”^[3] His answer came back in seven days.^[3]

Li Yuan’s officers urged him to accept. He refused.^[3] His counsellors Pei Ji and Liu Wenjing pressed him.^[3] The army had few war horses, they said. It did not need the Göktürk soldiers, but it could not do without the horses.^[3] They proposed a middle way. The emperor was to be honoured as retired emperor, and the prince of Dai was to be set up in his place. The army’s banners were to be changed to red mixed with white, to show the Göktürks.^[3] Li Yuan called it covering one’s ears to steal a bell. He agreed, because the times left him no choice.^[3]

Kang Shaoli’s horses

On the day dingyou of the sixth month Kang Shaoli and others came from the Göktürks with a thousand horses to trade.^[3] They promised that the khan would send troops to escort Li Yuan into the passes, as many as he wished.^[3] Li Yuan received the khan’s letter with great courtesy. He gave the envoys rich presents.^[3] He bought only half of the best horses. To his men, who wanted to buy the rest with their own money, he explained that the barbarians had many horses and loved profit. By taking few he showed that he was poor and in no hurry.^[3]

Then he sent Liu Wenjing to the Göktürks to ask for troops.^[3] In private he told Liu Wenjing what he wanted them for. Göktürk horsemen in China were a great bane to the people.^[3] He wanted them only so that Liu Wuzhou, the rebel of Mayi, could not bring them against the frontier. Their horses also grazed without costing fodder. More than a few hundred men would be of no use.^[3]

Liu Wenjing at Shibi’s court

In the seventh month Liu Wenjing reached Shibi. He asked for troops and made a bargain.^[3] If they took Chang’an, the people and the land would go to the duke of Tang, the gold, jade and silk to the Göktürks.^[3] Shibi was delighted. He sent his minister Jishi Tegin ahead to tell Li Yuan that the troops were on the march.^[3] In the same month Li Yuan left Jinyang with thirty thousand armoured men. The western Göktürk Ashina Danai followed him with his people.^[3]

The troops

On the day guisi of the eighth month Li Yuan reached Longmen. Liu Wenjing and Kang Shaoli came to him there with five hundred Göktürk soldiers and two thousand horses.^[3] Li Yuan was glad that they had come late.^[3] “I had reached the river before the Göktürks arrived,” he told Liu Wenjing, “and they bring few men and many horses. That is your work.”^[3]

The histories count the aid in four ways. The Jiu Tang Shu and the Tongdian give a thousand horses that met Li Yuan in the Jiang commandery and two thousand riders who helped to take the capital.^[4] The Xin Tang Shu gives two thousand horses and five hundred soldiers.^[5] The Zizhi tongjian gives a thousand horses for trade in the sixth month and five hundred soldiers with two thousand horses in the eighth.^[3] Some scholars put the aid at two thousand horses and five hundred riders. They call the aid decisive for Li Yuan’s first successes, above all at Huoyi in 617.^[2] In the Zizhi tongjian Li Yuan took Huoyi on the day xinsi of the eighth month, twelve days before the Göktürk troops reached him.^[3]

After the capital

Li Yuan took Chang’an and then the throne.^[1] The gifts he sent to Shibi could not be counted.^[1] Shibi relied on his merit and grew more and more arrogant. His envoys at Chang’an behaved as they pleased.^[6] The emperor put up with it, because the central plain was not yet at peace.^[1] Some scholars draw a conclusion from this. By helping the Tang to power, Shibi had unwillingly sealed the fall of the khaganate in the east and the west.^[7] The same Tang conquered the eastern khaganate in 630.^[1]