Emperor Dezong of Tang - Late Zhenyuan Era

Late Zhenyuan Era

Meanwhile, due to victories that Wei Gao and the Nanzhao king Yimouxun (異牟尋), who had become a Tang vassal after abandoning Tufan, were inflicting on Tufan, Tufan had become a much lesser threat to Tang security by this point.

By this time, Emperor Dezong's oldest son Li Song the Crown Prince had become close to the junior officials Wang Pi and Wang Shuwen, and Wang Pi and Wang Shuwen and their associates were planning on carrying out a number of reforms when Li Song would eventually be emperor. The officials who associated with them included Wei Zhiyi and such junior officials as Lu Chun (陸淳), Lü Wen (呂溫), Li Jingjian (李景儉), Han Ye (韓曄), Han Tai (韓泰), Chen Jian (陳諫), Liu Zongyuan, and Liu Yuxi. They essentially formed a shadow government.

In winter 804, however, Li Song suddenly suffered a stroke, causing him to be partially paralyzed and unable to speak. In spring 805, it was said that because of Li Song's illness, Emperor Dezong himself became severely depressed and fell into an illness. He died on February 25, 805, and, while there was some speculation both inside the palace and out as to whether Li Song would actually take the throne due to his severe illness, Li Song did so (as Emperor Shunzong).