however the region continued to experience disorders for the next 16 years. From 823 to 826, the Nung people (Huang people), aided by raiders from Champa, attacked Yongzhou and seized 18 counties. These raiders, known as the barbarians of the "Nung Grottoes" (Yellow Grotto Barbarians), sought aid from Nanzhao after the Tang retaliated from 827-835. In 845, governor Wu Hun tried to get his troops to rebuild the city walls of Songping but they rebelled and forced him to flee. The rebellion was put down. In 846 "barbarians" from Yunnan (Nanzhao) raided Annan. The new governor Pei Yuanyu counterattacked with soldiers from neighboring provinces. Rebellion, invasion, and renaming In 854, the new Jiedushi of Annan, Li Zhuo, provoked hostility with the mountain tribes by prohibiting the salt trade and killing powerful chieftains, resulting in the defection of prominent local leaders to Nanzhao. The general Lý Do Độc, as well as others, submitted to Nanzhao. In 858, Nanzhao invaded Annan while new jiedushi, Li Hu, killed the son of a chieftain who was implicated in a mutiny, further alienating powerful clans in Annan and causing them to defect to Nanzhao. While Nanzhao invaded in earnest, the Đỗ clan rebelled with 30,000 men. Then in early 863, Nanzhao and tribal allies took Songping after a bitter siege. There was general chaos as Nanzhao ravaged Annan, alienating the locals, and the balance of power see-sawed between Tang and Nanzhao forces. In 864, the experienced Tang general, Gao Pian, led a counterattack that saw the defeat of Nanzhao forces in 866. He recaptured Songping, the capital of Annan, and named the rebuilt capital Đại La. He also renamed the region of Annan to Jinghai Jun (lit. Peaceful Sea Army). Aftermath The Tang conducted a campaign against local tribes in Annan in 874-879. In 877, troops deployed from Annan in Guangxi mutinied. In 880, the army in Annan mutinied, taking the city of Đại La, and forced the military commissioner Zeng Gun to flee north, ending de facto Chinese control in Northern Vietnam. List of governors Protectorate governors Protectorate governors (都護) are civilian governors of the Protectorate. Military administration is held by Jiedushi (Military commissioner). During rebellion and wartime, the two position can be held by the same person. Liu Yanyou 劉延祐 681–687 Yang Min 楊敏 (During Wu Zetian's reign) Cui Xuanxin 崔玄信 (During Wu Zetian's reign) Guang Chuke 光楚客 Xin Ziyan 辛子言 He Lüguang