Imperial history: During the pre-Qin period, emperors, governors, doctors and city officials all set "Shi" as a historian and minister in charge of records. The monarch accepted the proposal. Since the Qin Dynasty, Shi Yu has been a supervisory official, in charge of supervising the imperial court and vassal officials until the Qing Dynasty. At the beginning of the Han Dynasty, Emperor Wen neglected his duty by remonstrating, and ordered the Prime Minister to send other personnel to stab him to death all over the country, which was not common. In the fifth year of Yuan Feng in Han Dynasty (BC 106), it was set up as "thorn", which means inquiry. The secretariat toured counties and counties, and was divided into thirteen departments (states) in China. Each department had a secretariat, which was later called the secretariat. In the middle and late Western Han Dynasty, the secretariat system was further developed, which played a positive role in maintaining imperial power, clarifying official management and promoting the formation of Zhao Xuan's resurgence. In the Xiao Dynasty, the secretariat was renamed, and its power was further expanded, from the supervisor to the local military chief.