Yan Changshan was originally a subordinate of An Lushan. After the Anshi Rebellion, Yan Changshan pretended to surrender because of insufficient troops, defended Changshan (now Zhengding, Hebei Province), and then recruited troops to capture Jingxing Pass, cutting off the back road of the Anshi Rebellion. Angry, Shi Siming was sent to surround Changshan, and Yan Gaoqing was arrested. Ann asked Yan if he had betrayed him. Yan said, "I am an official of the Tang Dynasty, and I will always be loyal. How can I rebel with a shepherd? " Ann was furious and ordered Yan's tongue to be cut off. Yan cursed until he died. Enduring the sharp pain of broken tongue, he still pursues the belief of loyalty.