Emperor Tang Xuanzong (唐玄宗) (685 - 762), born Li Longji (李隆基), was the sixth emperor of the Tang dynasty of China.

In 710 Xuanzong conspired with his aunt Princess Taiping to put an end to Empress Wei 's attempted usurpation of power. He killed Empress Wei, the wife of his recently dead uncle Emperor Zhongzong , in a palace coup which placed his own father, Emperor Ruizong , on the throne. Xuanzong himself succeeded the throne in 712.

Known also as Tang Minghuang, the early half of his reign (712-756) saw Tang China reach the height of her powers, in a period known popularly as the Kaiyuan era (開元之治). He is famous, amongst other things, as being a patron of the arts and for his infamous love affair with Yang Guifei. She was the young wife of his son Prince Shou (壽王), but he decreed their divorce and then entered her into a nunnery for a couple of years so that he could take her as his palace consort without shame. He rebuilt the ancient hot springs palace at the foot of Lishan Mountain for his consort and her sisters, naming it Huaqing Palace .

As Xuanzong turned his attention to pleasure-seeking with Yang and her family, he paid less and less attention to the running of his empire, and much of his power fell into the hands of court officials like corrupt Li Linfu (who was succeeded by Yang's dissolute cousin Yang Guozhong), and the influential court eunuch Gao Lishi.

In the meantime, the Jie Du Shi, (generals) of the outlying provinces (many of which had been recently reconquered) took more and more regional power into their own hands. One of these, a Turkish/Sogdian named An Lushan started the An Lushan Rebellion in Fanyang in 755. The rebels captured the city of Luoyang and the capital Chang'an six months later.

Xuanzong fled to Sichuan during the war, and Yang Guifei and Yang Kuozhong who attempted to flee with him were killed by the Imperial army for their perceived part in the Emperor's weakness and loss of control.

Xuanzong abdicated his position to Suzong , the heir apparent, and died in 762 shortly before the rebellion was finally quashed.

The strength that Xuanzong had allowed the warlords in the border provinces (Fanzhen ) led to a period of increasing conflict and instability which set the stage for the end of the Tang Dynasty and the ensuing Five Dynasties and Ten Kingdoms Period.

See also:

• minister Zhang Jiuling
• artist Wu Tao-Tzu