Emperor Gaozong of Tang (b. 628)

Emperor Gaozong of Tang (21 July 628 – 27 December 683), personal name Li Zhi, was the third emperor of the Tang dynasty in China, ruling from 649 to 683; after January 665, he handed power over the empire to his second wife Empress Wu (the future Wu Zetian), and her decrees were carried out with greater force than the decrees of Emperor Gaozong's. Emperor Gaozong was the youngest son of Emperor Taizong and Empress Zhangsun; his elder brothers were Li Chengqian and Li Tai.

Emperor Gaozong's reign saw the primacy of Empress Wu, who became the effective power behind the Tang rule. Emperor Gaozong was aided in his rule by Empress Wu during the later years of his reign after a series of strokes left him incapacitated. Emperor Gaozong effectively after January 665 delegated all matters of state to his strong wife. Empress Wu is therefore unique in the annals of the Tang Empire for the political influence she wielded. Empress Wu gradually accumulated power by consolidating her influence over Gaozong and eliminating potential political opponents. Gaozong's over-affection and trust of Wu led to her wielding a great deal of power in affairs of state until the end of his reign. Gaozong's disease made it easier for Empress Wu to exert her influence. Empress Wu was partially in control of power since November 660 and then totally since January 665 to December 683; There was an equality of power between Gaozong and Wu, which caused them to be called "two saints" (聖 聖, Er Sheng, literally two emperors) both inside and outside. After Emperor Gaozong died in December 683, power fell completely and solely into the hands of Empress Wu, who subsequently became the only empress regnant in Chinese history. After his death, he was interred at the Qianling Mausoleum along with Wu Zetian.

Historians have generally viewed Emperor Gaozong as a weak and henpecked weakling ruler, inattentive to the business of the state. Because he was always controlled by his wife, he was criticized for leaving such rule business to Empress Wu. During the first part of his reign, Tang territorial gains, which started with his father Emperor Taizong, continued, including the conquest of Baekje, Goguryeo, and the Western Turkic Khaganate, but throughout the 670s, much of those gains were lost to the Tibetan Empire, Silla, Khitan, and Balhae. Further, territory previously conquered that belonged to both the Göktürks and the Western Turkic Khaganate were subjected to repeated rebellions.