The history of Chinese/Turkic interactions may go back to the interactions between the Xiongnu people and the Chinese in pre-Imperial/early Imperial China. Though there is still much debate as to who exactly the Xiongnu were, or whether they were identical to the Huns, the prevailing theory is that the Huns were the Xiongnu, and archeological and linguistic evidence suggests a Turkic origin for them.¹

The Huns and later the Turks conquered and assimilated different peoples they encountered, so neither the ancient Huns or the medieval Turks could be described as ethnically homogeneous.² Genetic research suggests that the Huns were a confederation of Turkic, Ugric, Finnic, Tungus and Mongolic peoples.³ Migrating from their homelands in Northeast Asia, the Turkic peoples of antiquity intermarried with the native Indo-Iranians in Central Asia and West Asia, creating hybrid Turko-Iranian cultures.⁴

Turkic Central Asians came to China during the Yuan Dynasty as bureaucrats, soldiers and merchants, forming part of the semuren class.⁵ People from Central and West Asian lands conquered by the Mongols were brought to China to help the Mongol elite govern the locals.⁶ The Salars (a subgroup of the Huns) migrated from Uzbekistan to Northwest China in the 14th century-15th century.⁷ They are described as Caucasoid by a Chinese source:

The Salars have their own independent language, naturally different in basic vocabulary and grammatical structure from the languages of the surrounding Han and Tibetan peoples. It is close to the languages of the Turkmen and the Uzbeks living in Samarkand. They all belong to the Yugus branch of the Western Xiongnu (Hun) group of the Turkic languages, which are part of the Altaic language family. The Salars' relatively tall and large physique, abundant facial hair, high-bridged noses, and deep-set eyes and other external features clearly mark their differences from the neighboring Han and Tibetan peoples and prove they have a close racial resemblance to the peoples of Central Asia.⁸

The Salars were Oghuz Turks who intermarried Mongols, Tibetans, Chinese and Huihui (Chinese-speaking Muslims).⁹

Notable Chinese-Turkic individuals and unions

According to "Examples from the Chaos: Personalities of the Troubled Times in Chinese History" from Shandong Huabao Publishing Company, Li Bai, one of the four great poets of Chinese history, was of Xiongnu (Hunnic) descent. His ancestor Li Ling was a general of the Chinese Han Dynasty and grandson of the famous Chinese general Li Guang. In 99 BCE, Emperor Wu of Han sent Li Ling against a 30,000-strong Xiongnu cavalry with 5000 Chinese infantry soldiers. Despite their valiant efforts in exterminating about a third of the enemy, Li Ling and his soldiers ran out of ammunition when the expected Chinese reinforcements did not arrive. The Xiongnu king summoned an additional 80,000 troops and Li Ling surrendered after a desperate battle.

Emperor Wu of Han, angered at this defection, ordered the castration of Sima Qian, the only courtier who dared to speak up in defense of Li Ling. Yet later, the Chinese ruler repented of judging Li Ling's actions too harshly. In 97 BCE, the Emperor sent Gongsun Ao deep into Xiongnu territory to retrieve Li Ling, but Gongsun was defeated by the Xiongnu forces. To cover up for his failure, Gongsun told Emperor Wu that Li Ling had trained the Xiongnu troops. The enraged Emperor executed Li Ling's family, including his wife and his mother, only to realize later that Gongsun's report was false. Disillusioned with the Han Dynasty, Li Ling accepted the daughter of the Xiongnu king in marriage and lived among the Xiongnu to the end of his days.¹⁰

Li Ling's Xiongnu descendants became part of the Xiajiasi/Jiankun Kingdom. The people of Xiajiasi were described in the 1060 historical work New Chronicles of the Tang Dynasty as "tall, red-haired, ... green-eyed; they regard black hair as inauspicious, and say that those with black eyes are descendants of Ling..."¹¹

Centuries later, Li Ling's 23rd generation descendant Li Bai (701-762) moved to China from his native Kyrgyzstan at age 4.¹² Upon returning to China, Li Bai's father took up their ancestral Chinese surname of Li.¹³

During the time of the frontier wars between the Chinese and the Xiongnu, Chinese women were sent as brides to the royal house of the Xiongnu to help secure peace between the nations.¹⁴ The most famous of these 'peace brides' was Wang Zhaojun (52 BCE - 19 BCE), one of the Four Great Historical Beauties of China. She married the Xiongnu king Huhanxie, with whom she had a son Yituzhiyashi. Huhanxie, being much older than Zhaojun, died shortly after the birth of their son.

After Huhanxie's death, Wang Zhaojun was required by Xiongnu custom to marry her husband's son and heir. Such a practice was against Chinese custom; Wang Zhaojun wrote to the Chinese imperial court, asking permission to return home. The Emperor refused her appeal, so the young widow had to marry Diaotaomogao, Huhanxie's eldest son by Huhuanxie's principal queen. She bore the new king two daughters, Princess Pu and Princess Yu. Zhaojun passed away a year after her second husband's death.¹⁵

Notes:

1. Wikipedia entry on Huns Wikipedia entry on Turkic peoples Wikipedia entry on Xiongnu
2. Wikipedia entry on Huns Wikipedia entry on Turkic peoples
3. Wikipedia entry on Huns
4. Wikipedia entry on Iranian peoples
5. Baidu entry on semuren
6. Central Asians in Mongol China: Experiencing the 'Other' from Two Perspectives Jonathan Lipman, Familiar Strangers: A History of Muslims in Northwest China
7. Wikipedia entry on Salar
8. Lipman, p17
9. Wikipedia entry on Salar Lipman, p18
10. Li Guang
11. Li Ling, the secret of Li Bai's family
12. Li Bai on Baidu Encyclopedia
13. Li Ling, the secret of Li Bai's family
14. The Division and Destruction of the Xiongnu Confederacy in the first and second centuries AD
15. Wang Zhaojun on Baidu Encyclopedia