Princess Taihe

Princess Taihe (太和公主, personal name unknown), later, in 843, known as Princess Ding'an (定安公主) or Princess Anding (安定公主), was a princess of the Chinese Tang dynasty and a khatun (empress) of the Uyghur Khaganate. She was married to the Uyghur Chongde Qaghan as part of the Heqin system of marriages between Tang princesses and Uyghur qaghan, and she was later subject to the Uyghur levirate marriage system. She suffered through the Uyghur Khaganate's subsequent collapse before being welcomed back to the Tang court. As the last Tang princess to be part of the Heqin system, Taihe marked the end of the marriage alliances between the Tang dynasty and Uyghurs.

Background and entry into marriage It is not known when Princess Taihe was born, although it is known that she was a daughter of Emperor Xianzong (r. 805–820) and Emperor Xianzong's wife Consort Guo, and that she was younger than her full brother Li Heng, who was born in 795. She was Xianzong's 10th daughter over all.

Late in Emperor Xianzong's reign, the Uyghur Khaganate, ruled by Baoyi Qaghan, made repeated overtures to request a Tang princess to be married to Baoyi under the Heqin system. Eventually, after a mission headed by the Uyghur diplomat Hedagan (合達干), Emperor Muzong (r. 820–824) agreed to have Princess Taihe's older sister Princess Yong'an married to Baoyi, but as Baoyi died in 821, the marriage never took place. Soon after, Princess Yong'an requested to be ordained as a Daoist priestess, thus avoiding future marriage alliances. Princess Taihe departed Chang'an, the Tang capital, escorted by the general Hu Zheng (胡証), assisted by the other officials Li Xian (李憲) and Yin You (殷侑). Anticipating a possible attempt by Tibetan forces to intercept Taihe's train, Uyghur forces were dispatched to escort them as well as to attack Tibet's borders. Princess Taihe remained in the Uyghur Khaganate, and under the Uyghurs' levirate marriage custom, In 832, Zhaoli was assassinated by his subordinates, and his nephew Yaoluge Hu succeeded him as Zhangxin Qaghan.

In 839, after a rebellion by the officials Anyunhe (安允合) and Chaile (柴勒), Zhangxin Qaghan was able to defeat and kill them, but a subsequent attack by another official, Jueluowu (掘羅勿), along with the Shatuo chief Zhuye Chixin, defeated Zhangxin, and he committed suicide. The nobles supported another member of the royal family, as Qasar Qaghan. That year, it was said that in addition to these wars, there was a major plague and major snow storm, causing many deaths of the Uyghur's livestock and leading to the Khaganate's sudden decline.

In 840, a major Kyrgyz attack on the Uyghur Khaganate destroyed the Uyghur headquarters, and both Qasar Qaghan and Jueluowu were killed in battle. The remaining Uyghur forces scattered. In 841, one of the major generals, Wamosi, submitted to Tang (which was then ruled by Emperor Muzong's son Emperor Wuzong), and Emperor Wuzong issued an edict to Wamosi ordering him to seek out Princess Taihe. Meanwhile, Taihe was taken captive by the Kyrgyz khan Are (阿熱), and Are, who claimed ancestry from the Han dynasty general Li Ling and thus a common ancestry with Tang emperors (through Li Ling's grandfather Li Guang), treated her with respect and sent a group of generals to escort Taihe back to Tang territory. On the way, one of the remnant Uyghur leaders, Wujie Qaghan, ambushed the Kyrgyz escort and took Taihe. He had her write to Wuzong requesting that him make him the new qaghan and also lend the border city of Zhenwu (振武, in modern Hohhot, Inner Mongolia) to him to allow him to plan the rebuilding of the Uyghur Khaganate. Wuzong responded with an edict that instructed Wujie to remain outside Tang borders and requested Taihe to personally return to Chang'an to report on the Uyghur Khaganate's status.

After return to Tang On April 4, 843, Princess Taihe arrived at Chang'an. Emperor Wuzong ordered the chancellors and the other officials to welcome and honor her. Volume 76 of the Quan Tang Wen includes the imperial edict, which roughly translates to:

She took off her grand clothes and jewels, and she approached the palace, apologizing for the failure of her mission. Emperor Wuzong sent eunuchs to comfort her and put her robes and jewels back on, and then welcomed her into the palace. The next day, she had a reunion with her mother Grand Empress Dowager Guo, and she was made Grand Princess Ding'an (per the New Book of Tang) or Grand Princess Anding (per the Zizhi Tongjian). Seven princesses did not attend the welcoming ceremony, and Wuzong, in anger, took away a portion of their stipend and the silk customarily given to them.

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