Zhang Liao was both courageous and keen-minded. He was a descendant of Nie Yi in the Eastern Han Dynasty. To avoid envy and hatred of other people, his family name was changed to Zhang. First he aided Ding Yuan, and then followed Dong Zhuo and served under Lu Bu. Lu Bu relied on him as one of his commanders. Zhang Liao was captured when Cao Cao overthrew Lu Bu at Xiapi. He was kindly treated and followed Cao Cao thereafter, then he was sent on a mission to win over the bandit leader Zang Ba. Later Cao Cao used him to woo Guan Yu from Liu Bei. He persuaded Guan Yu to surrender to Cao Cao. Initially Guan Yu resisted and threatened to commit suicide, but Zhang Liao reminded him of his oath. "If you die now you will be guilty of breaking three promises, your pledge to live and die as one with Liu Bei, your responsibility as the caretaker of Liu Bei's family, and your promise to restore the Han Dynasty to glory. Yield to Cao Cao for now."
     Guan Yu responded with three conditions for his surrender. "Firstly, I will not defer to Cao Cao, but to the Emperor of Han. Next, I must be assured of the safety of Liu Bei's family. Lastly, I must be allowed to leave Cao Cao's side the moment I learn of Liu Bei's whereabouts." Zhang Liao agreed to these terms. Zhang Liao proved his worth under Cao Cao. He aided Cao Cao in his conquest all across the land. Most celebrated are the two times his tactics defended Hefei from Sun Quan. The first time, he was preparing for an attack when a fire broke out within the city wall amidst cries of "Tyranny!"
     "The whole city could not be full of traitors," said Zhang Liao, and he traced down the trouble-starters, who were from Wu. As this was just an attempt by Sun Quan to throw him from his own castle. Zhang Liao reversed the plan to his benefit. He ordered cries of "Tyranny! Treachery!" to ring out again, and threw open the city gates. The Wu army marched in their offensive and was greeted by a shower of arrows. The ambush killed Taishi Ci, a great warrior of Wu.
     In the second instance, Zhang Liao fended off a ten thousand man army. Cao Cao was on an expedition to overthrow Zhang Lu, and had left instructions in case of an attack. They read, "If Sun Quan should invade, Zhang Liao and Li Dian are to lead the army to battle. Yue Jin is to guard the castle walls." The generals were hesitant to follow the orders, but Zhang Liao explained, "If we remain on the defensive, we will be destroyed before reinforcements arrive. The letter instructs us to intercept the enemy's advance guard. Then once we have broken their spirits, we can resume a defensive stance." Having roused their fighting spirit, the generals rounded up brave soldiers, and fended off their opponents with merely 800 men. It is said that the name of Zhang Liao kept the children of the South Land quiet at night. Cao Pi, the founder of the Wei Kingdom, later compared Zhang Liao to the warlords of old, who overcame threatening enemies for the preservation of the empire.
     In 224 AD, Cao Pi led a huge army to subdue Wu. Zhang Liao was appointed as one of his Chief Commanders. He rode ahead but was wounded by an arrow of Ding Feng in the loins. He was helped away by Xu Huang and got back to Xuchang. Unfortunately, his wound was deep and he died at the age of 64.