Li Deyu, courtesy name Wenrao, formally the Duke of Wei, was an official of the Chinese dynasty Tang Dynasty.
Background
Li Deyu was born in 787, during the reign of Emperor Dezong. His grandfather Li Qiyun served as the chief imperial censor, and his father Li Jifu would eventually serve as a chancellor during the reign of Emperor Dezong's grandson Emperor Xianzong. It was said that Li Deyu was ambitious in his youth and was studious, particularly concentrating on the Book of Han and the Zuo Zhuan. He, however, did not want to submit to imperial examinations. During Emperor Dezong's Zhenyuan era (785-805), when Li Jifu was in exile, Li Deyu accompanied his father and did not seek an official career.
Career
Li Deyu was an official of the Chinese dynasty Tang Dynasty, serving as a chancellor during the reigns of brothers Emperor Wenzong and Emperor Wuzong and (briefly) their uncle Emperor Xuānzong. He was the leader of the so-called Li Faction in the decades-long Niu-Li Factional Struggles, and was particularly powerful during Emperor Wuzong's reign, dominating the court scene and guiding policies during the campaigns against the crumbling Huigu Khanate and against the warlord Liu Zhen. After Emperor Wuzong's death, Emperor Xuānzong, who had long despised him for his hold on power, had him demoted and exiled, and he died in exile.