Bai Juyi
In 819, Bai Juyi was recalled to the capital and given the position of second-class Assistant Secretary. In 821, China got a new emperor, Muzong. After succeeding to the throne, Muzong spent his time feasting and heavily drinking and neglecting his duties as emperor. Meanwhile, the temporarily subdued regional military governors, "jiedushi", began to challenge the central Tang government, leading to the new de facto independence of three circuits north of the Yellow River, which had been previously subdued by Emperor Xianzong. Furthermore, Muzong's administration was characterized by massive corruption. Again, Bai Juyi wrote a series of memorials in remonstrance.