For officials during the Tang Dynasty, achieving military credits was animportant way to obtain promotions. For this reason, officials with civilbackground would still choose to participate in military missions. In the first halfof the Tang Dynasty, the fact that some officials moved back and forth betweencivil and military positions has attracted the attention of modern historians. Afterthe An Lushan Rebellion (755-763), however, professional soldiers expandedtheir power, while the court failed to control the armies effectively. Under thiscircumstance, most civil officials lost the opportunity to manage military affairs,but some of them still attempted to follow the early Tang tradition. Throughproviding military opinions to the court and advocating military learning amongliterati, some civil officials tried to regain military leadership. In their mind,appointing civil officials to military command positions could undermine theinfluence of military men and strengthen the imperial authority. In the secondhalf of the Tang, thus, when the emperor tried to expand the central authority, hecould appoint civil officials to manage expeditions against insubordinate militarygovernors. However, due to the fact that late Tang civil elite usually lackedmilitary talents, most civil commanders failed to achieve substantial credits.Thus, the efforts literati made to regain military leadership failed to increase the ruling power of Tang court. Along with the significant decline of Tang centralauthority in the late ninth century, the military participations of civil officialsalso came to an end.