Who could be appointed as prime minister by six different states at the same time? Who could make the whole world tremble when angry and bring peace when at rest? Who could dominate the political stage of the Warring States period with exceptional eloquence and wisdom? The only person who could achieve this was likely Su Qin, a master of rhetoric and diplomacy.
Su Qin, courtesy name Jizi, was a native of Luoyi in the Eastern Zhou. He came from a poor family but harbored great ambitions; it is said that he once studied the art of political maneuvering with Zhang Yi under the master Guiguzi. After completing his studies, he sought to display his talents in the state of Qin. So, taking his travel funds, he went to Qin and repeatedly presented his ideas to the King of Qin, but never gained the king's favor. When his money ran out and his clothes became worn, he had no choice but to return home.
When he returned home, he was dressed in rags, wore straw sandals, and was so hungry that he had become thin and dark. Upon arriving, his wife did not greet him, his sister-in-law refused to cook for him, and even his parents found him disgraceful and ignored him. Su Qin felt deeply upset, so he resolved to achieve great success. From then on, he studied diligently every day until late at night. To prevent himself from dozing off, he tied his hair to a beam with a rope and held an awl in his hand. Whenever he grew drowsy and his head began to droop at night, the rope would pull painfully at his scalp; when he was too sleepy to continue, he would prick his thigh with the awl to stay awake. After a year of such hard study, he finally developed the strategies of vertical and horizontal alliances.
At that time, among the feudal states, there were seven relatively powerful ones: Qi, Qin, Chu, Yan, Zhao, Han, and Wei. Among them, Qin was the strongest and frequently invaded other states. Just as Su Qin was about to promote his strategy of vertical alliance, a war broke out between Qin and Zhao. Yan was a neighbor of Zhao, so Su Qin went to the state of Yan to seek an audience with the King of Yan. He said, "If Qin attacks Yan, it would previously have to march several thousand li to reach it. But if Qin defeats Zhao, then attacking Yan would only require a journey of a few dozen li. Yan and Zhao are like lips and teeth—if the lips are gone, the teeth will feel cold. Therefore, Your Majesty, forming an alliance with the King of Zhao to resist Qin is actually protecting yourself!" Consequently, Yan agreed to send troops to help Zhao jointly confront Qin.
Subsequently, Su Qin went to visit the King of Zhao. He said to the king, "I have heard that the lands of some border states are five times the size of Qin, and I suspect that the combined lands of the six states are ten times that of Qin. If the six states unite to attack Qin together, then Qin will surely be destroyed." Then Su Qin suggested, "Let the generals of the six states form an alliance at the Huan River, with Chu, Qi, and Wei each sending elite troops to resist the mighty Qin, Han providing provisions for these three states, and Yan defending north of Changshan against Qin forces. At that time, if Qin attacks Han or Wei, Chu will cut off Qin's rear, Qi will respond by sending troops to support Chu, and Zhao and Yan will each hold their positions to resist Qin's army. In this way, Qin can be defeated." Su Qin then analyzed in detail how the six states should resist if Qin attacked any of the other five. His arguments were well-reasoned and supported by evidence, and the King of Zhao applauded in admiration. Subsequently, the king bestowed upon him ten thousand gold pieces, a hundred pairs of white jade discs, and numerous rolls of fine silk and brocade, commissioning him to persuade the other states.
At that time, when Su Qin advised the King of Qi to adopt the strategy of forming a vertical alliance to resist Qin, the king harbored concerns about the state of Yan. Su Qin then said to the King of Qi, "The state of Yan is weak in national strength and has always relied on Qi, and it was with Yan's considerable help that Qi was able to command the allegiance of all under heaven. How could the people of Yan possibly harbor disloyal intentions toward Qi?" Only then did the King of Qi set aside his worries and join the anti-Qin alliance.
Starting in 334 BC, Su Qin began traveling to the six states to lobby for his "Vertical Alliance" strategy, and within just one year, he achieved great success; under his orchestration, the six states decided to hold a blood oath alliance at the Huan River in the State of Zhao to jointly resist the State of Qin, at which point Su Qin was appointed as prime minister by the six feudal lords, gaining immense fame and prestige.
When Su Qin returned to his hometown in glory, his parents, upon hearing the news, immediately cleaned the house and sent people to welcome him from dozens of miles away in the outskirts. His wife did not dare to lift her head to look at him. His sister-in-law knelt on the ground and apologized to him. Seeing this scene and recalling how they had treated him before, Su Qin was overwhelmed with a mix of emotions.
Su Qin traveled among the six states to persuade them to form an alliance, but in reality each state had its own agenda and they checked one another, so no fundamental progress was made. Later, Zhang Yi broke Su Qin's strategy of vertical alliance, and the coalition of the six states collapsed.