In 506 BC, on the recommendation of Wu Zixu, King Helü of Wu appointed the great military strategist Sun Wu as his supreme commander, reorganized his troops, and prepared to attack the state of Chu.
Sun Wu was a native of Qi, who described himself as a humble farmer from the eastern coast. He had come south to Wu at the invitation of Wu Guo, a minister of Wu. His passion lay in studying military strategy, and he held fame and wealth in low regard. The reason he agreed this time to take up the prestigious position of commander-in-chief was twofold. First, he wanted to help his old friend Wu Zixu achieve his goal of defeating Chu. Wu Zixu was originally from Chu; his father and elder brother had been murdered by the foolish King Ping of Chu, and he had been a refugee in Wu for over ten years, never forgetting his desire for revenge. The second reason Sun Wu accepted the post was that he had completed a military treatise consisting of thirteen chapters, including "Laying Plans," "Waging War," "Strategic Attacks," "Military Postures," and "Force." He was eager to test his theories in actual combat, to see how effective his strategies were in war and whether they needed further refinement.
However, although Sun Wu had accepted the appointment as Wu's commander, he felt somewhat uneasy. This was because he had once executed two of King Helü’s favorite concubines, Xia and Jiang, and he feared the king still harbored resentment, which might lead to friction later and end their collaboration on bad terms.
The story of Sun Wu executing the beautiful concubines Xia and Jiang is a famous historical event. When Sun Wu first arrived in Wu, King Helü often invited him to lecture on tactics and military doctrine. Sun Wu cited numerous famous battles from history, analyzing in detail the reasons for victory and defeat, and the king listened with great interest. However, the king did not blindly accept everything; where he didn’t understand, he would often argue with Sun Wu. For instance, Sun Wu said: "The outcome of war depends largely on the skill of the military commander. An outstanding commander can mobilize thousands of troops as effortlessly as moving his own limbs." He also said: "Not only that, an excellent commander can turn weak troops into strong ones. Even delicate women can be trained to become as strong and brave as soldiers." The king did not believe this, saying, "How can women be trained into an army? That's impossible!" Sun Wu replied, "If Your Majesty doesn't believe me, we can try it. Give me your palace maids and concubines to train, and I guarantee they'll be ready for battle within a month!" Wanting to test Sun Wu's abilities, the king agreed and handed over more than a hundred palace women for training.
Sun Wu divided the women into two units, appointing Concubines Xia and Jiang as leaders. He announced strict discipline, stating that during military training, regardless of any excuse, all must obey orders without question. Anyone disobeying commands would face severe punishment under military law, including execution. These pampered palace women treated Sun Wu's words as idle chatter. Especially Xia and Jiang, who were heavily made-up and giggling, moved slowly and carelessly, as if strolling through a scenic garden.
When Sun Wu ordered them to move east, they deliberately went west, looking at him disdainfully. Unable to endure any longer, Sun Wu sentenced both women to death for violating orders. The king deeply mourned the loss of his beloved concubines. Though he said nothing publicly, he was inwardly very upset. Had it not been for Wu Zixu intervening promptly with explanations, the king had planned to ceremoniously send Sun Wu out of the country.
Wu Zixu noticed Sun Wu's lingering doubts and prepared wine and food, sharing a drink and heart-to-heart talk with his old friend. He said, "At first, the king was indeed furious with you. Later, I advised him: 'What Sun Wu did was right. An army must have iron discipline. Without obedience, it's just a disorganized mob incapable of winning battles. Since the king entrusted the palace women to him for training, they became his soldiers. It is perfectly justified for a general to punish soldiers who violate military discipline. If the king wishes to dominate the Central Plains, he needs someone like Sun Wu to train a powerful army. We must never lose a generation-defining general over two women!' The king is an enlightened ruler; once explained, he understood immediately, and his anger subsided. Later, when he saw those frail palace women transformed into vigorous soldiers after your training, he greatly admired you. Otherwise, since you're not even from Wu, why would he confidently appoint you as supreme commander?" Hearing Wu Zixu's words, Sun Wu realized the king was indeed magnanimous and thus settled his mind, ready to fully pursue his ambitions.
After appointing Sun Wu as commander, King Helü held a grand banquet to celebrate. During the feast, the king said, "My lifelong ambition is to dominate the Central Plains and let us southerners hold our heads high. But Chu, relying on its vast territory and large population, opposes us at every turn. Therefore, to achieve dominance, we must defeat Chu. Furthermore, Minister Wu's family has been loyal and meritorious, serving King Ping of Chu faithfully in governing and defending the realm. Yet, shamefully, King Ping listened to the slander of the treacherous minister Fei Wuji, killed Minister Wu's father and brother, and sought to exterminate his entire line by pursuing him. Poor Minister Wu fled here to Wu to escape assassination, his hair turning white overnight passing the Zhaoguan Pass. I am determined to avenge Minister Wu and crush Chu. General Sun, what are your thoughts on attacking Chu?" Sun Wu replied, "We must fight Chu. However, King Ping of Chu, who persecuted Minister Wu, has been dead for several years. His successor, King Zhao of Chu, has ruled diligently and strengthened the state. If we attack recklessly, we could easily fail. War concerns the survival of the nation and life or death for the people. It requires thorough consideration and careful planning before making a decision. Most people think victory depends solely on brute force, but that is not true. Deciding outcomes by force alone is the inferior approach; achieving victory without fighting is the superior strategy!"
The king was puzzled and asked, "War means two armies facing each other to decide victory or defeat. How can one win without fighting?" Wu Zixu was also confused and urged Sun Wu, "What brilliant method do you have? Quickly tell us so we can hear it." Sun Wu smiled slightly and said, "There are four methods to achieve victory. First, 'attacking strategy' (Fa Mou): anticipate the enemy's intentions, strike first, overwhelm them psychologically, sap their morale, and thereby gain victory—this is the superior strategy. Second, 'attacking alliances' (Fa Jiao): carefully study the enemy's allies, break their coalition, and weaken their strength—this is the middle strategy. Third, 'attacking troops' (Fa Bing): engage in battle, using force to win—this is the inferior strategy. Fourth, 'attacking cities' (Fa Cheng): capturing a city by assault. Because the enemy defends stubbornly, great cost is required for victory—this is the worst strategy."
Wu Zixu said, "I understand now. To attack Chu, we should primarily use 'attacking strategy' and 'attacking alliances,' supplemented by 'attacking troops,' correct?" The king also became interested and asked, "Exactly how do we carry out 'attacking strategy' and 'attacking alliances'?" Sun Wu said, "There are many ways to weaken the enemy. For example, though we are strong, we can deliberately pretend to be weak, causing the enemy to underestimate us and lower their guard. Or, we can use spies to sow discord among the enemy's key ministers, creating internal strife. These methods belong to 'attacking strategy'!" Wu Zixu repeatedly praised these methods as ingenious and asked Sun Wu, "How should we conduct 'attacking alliances'?" Sun Wu said, "To be specific, currently Chu has formed an alliance with the two small states of Tang and Cai. If we attack Chu, Tang and Cai will certainly come to its aid and oppose us. Therefore, we must use diplomatic means to win over Tang and Cai—that is the strategy of 'attacking alliances.' Once Tang and Cai remain neutral or even assist us in attacking Chu, King Chu will be unable to withstand us!" The king and Wu Zixu both praised this plan highly, admiring Sun Wu's wisdom and far-sighted strategy, and decided to proceed accordingly.
Meanwhile, King Zhao of Chu heard that King Helü of Wu had appointed Sun Wu as commander and was actively preparing for war, filling him with anxiety. One night, the king had many nightmares. Upon waking in the morning, he felt dizzy. Feeling his eyelids dry, he walked to a table by the window to retrieve a bronze mirror to look at his face. Suddenly, he noticed a sword lying atop the mirror. Picking it up, he saw that the blade emitted a blue luster in the morning light—it was a fine sword.
This was not the sword the king usually wore; that one still hung on the wall. Compared to this new sword, the king's own appeared inferior. Who had placed this sword here? The king found it extremely strange, summoned his maidservants to inquire, but no one knew. Deeply unsettled, he called upon the Right Lingyin Nang Wa to discuss the matter.
Nang Wa flattered him, saying, "It must be because Your Majesty governs wisely and possesses high moral virtue, thus touching Heaven, which sent a deity to deliver this precious sword to you. Otherwise, with the inner palace so strictly guarded that not even a bird could fly in, how could anyone enter the king's bedroom?" The king was delighted by this explanation and carefully stored away the sword.
Soon after, a blacksmith named Feng Hu arrived in Chu's capital, claiming to be from Yue. Feng Hu was renowned throughout the land not only for forging excellent swords but also for identifying various famous blades. Many sword enthusiasts in Chu invited Feng Hu to appraise their weapons. No matter the sword, Feng Hu could identify its maker, date of creation, and characteristics with just a glance. This news quickly reached the king, who summoned Feng Hu to the inner palace to authenticate the mysterious sword.
Feng Hu drew the sword from its sheath; there was a loud "zing" sound, and the blade seemed like lightning piercing his eyes. Feng Hu gasped, placed the sword back on the table, bowed deeply before it in reverence, and murmured something under his breath. This ghostly behavior bewildered the king, who stared wide-eyed at Feng Hu. Feng Hu's voice grew louder: "My apologies, Zhanlu! I didn't know you had come here—I've failed to welcome you properly!" The king asked, "Who is Zhanlu? Where is he?" As if suddenly awakened from a dream, Feng Hu hastily replied, "Your Majesty, 'Zhanlu' is the name of this sword. It was forged by Ou Yezi, a master craftsman from Yue. Once, the King of Yue commissioned Ou Yezi to create five precious swords, three of which were gifted to King Helü of Wu. The king named these three: Zhanlu, Pan Ying, and Yu Chang. Zhanlu is the finest of the three, arguably the greatest sword in the world. It was secretly kept by the King of Wu—how could it have ended up in Chu? What a marvel, what a marvel!"
Upon hearing that the sword he possessed was the legendary Number One Sword in the world, the king's eyes lit up with joy. Yet, he remained worried about its mysterious origin: "Since this sword was secretly kept by the King of Wu, how did it suddenly appear in my bedroom the other morning? Is this an omen of good or ill fortune?" After pondering for a long time, Feng Hu suddenly clapped his hands and said, "I remember now! Ou Yezi was my friend. He once told me this sword was forged from the essence of five metals, the spirit of the sun, and the soul of heaven and earth. Worn at the waist, it greatly enhances one's authority; drawn, it invokes the aid of a hundred deities. Only a rightful king may possess it. This sword also possesses spirit; if its owner acts unrighteously, it will angrily depart and seek a virtuous ruler. Thus, we know this sword left the King of Wu due to his lack of virtue and came to serve Your Majesty instead."
The king suddenly recalled the Right Lingyin Nang Wa's earlier claim that a deity had delivered the sword. Since both accounts matched perfectly, he believed it must be true. Despite the complete nonsense, the king firmly believed it and laughed triumphantly, "Heaven is most just, most just indeed!" Then he suddenly stopped laughing and asked Feng Hu, "The King of Wu had three swords. Are the other two still around?" Feng Hu replied, "Pan Ying was buried with the king's only daughter when she died of illness. Yu Chang has turned into a pile of scrap iron. Your Majesty knows that King Helü of Wu murdered his cousin, King Liao, usurped the throne, and used the Yu Chang sword to hire an assassin for the killing. Such an immoral act stripped Yu Chang of its divine power, turning it into useless scrap." The king's worries finally eased. He said, "Thus, the King of Wu now possesses no precious swords; he has been abandoned by Heaven. From now on, I need not fear him anymore!" He rewarded Feng Hu with much gold. After receiving the gold, Feng Hu left Chu for Wu. In reality, all of this had been secretly arranged by Sun Wu. The sword had been delivered into the Chu palace by a hired expert thief. Feng Hu's bizarre behavior and words were also orchestrated by Sun Wu.
Through this covert "attacking strategy" maneuver, Sun Wu subtly caused the king of Chu to become arrogant and contemptuous of Wu. Overconfident armies are destined to fail. With minimal cost, Sun Wu had already led the king of Chu down the first step toward defeat.
Sun Wu intended to lead the king of Chu down the second and third steps to ruin. He closely monitored the movements of Chu's allies, the two small states of Tang and Cai, seeking opportunities to sow discord.
The opportunity finally came. His spy returned from Chu reporting that the Right Lingyin Nang Wa had offended the rulers of Tang and Cai, who deeply resented him.
Here's what happened: Tang and Cai paid tribute to Chu annually. This year, Marquis of Tang brought a famed thousand-li horse, and Marquis of Cai brought a valuable fox-fur coat, traveling to Chu to present them to the king. Desiring these treasures, Nang Wa dispatched men to intercept them halfway, preventing them from seeing the king or leaving Chu.
A minor officer under the Marquis of Tang, quick-witted, thought, "Why should our lord remain stranded in Chu over a single horse?" So, in the dead of night, he stole the thousand-li horse and presented it to Nang Wa, saying, "My lord praises your lofty virtue and high standing, and specially instructed me to offer this steed!" Nang Wa immediately released the Marquis of Tang, allowing him to return home. Upon learning of Tang's escape method, the Marquis of Cai also gave his fox-fur coat to Nang Wa. As Cai left Chu's border, he muttered angrily, "Such humiliation! Though I rule a weak state, one day I will cross this border and kill that old villain Xiangwa!"
Sun Wu immediately sent a fox-fur coat and a letter to the Marquis of Cai in King Helü's name. The letter read: "I heard the Right Lingyin of Chu seized Your Majesty's beloved fox-fur coat. I am shocked. Though Chu is strong, Nang Wa is merely a subject. Though Cai is weak, Your Majesty is a sovereign king. How dare a subject forcibly seize possessions from a monarch? As a fellow king, I am deeply angered by Nang Wa's actions. I specially send this fox-fur coat as a token of sympathy." Upon reading the king's letter, the Marquis of Cai shed tears. He thought, "Chu is strong, but Wu is also strong. Perhaps it's better to ally with Wu."
The Marquis of Tang also received a thousand-li horse and a letter from King Helü. He too shed tears and prepared to align himself with King Helü.
A few days later, envoys from Cai and Tang secretly arrived in Wu, formally declaring an alliance with Wu to jointly confront Chu. After sending off the envoys, King Helü happily said to Sun Wu, "General, your brilliance is unmatched! Without deploying a single soldier, you've secured fifty thousand troops from Cai and Tang!" Wu Zixu said, "The king of Chu loses fifty thousand, we gain fifty thousand—netting a hundred thousand troops! Your Excellency's 'attacking alliances' strategy truly works!" King Helü turned to Sun Wu and asked, "General, can we now launch our campaign against Chu?" Sun Wu replied, "The king of Chu, believing Feng Hu's words, has lost his vigilance. Tang and Cai have secretly defected, further weakening his strength. The conditions for attacking Chu are now ripe. However, there is one more thing we must do before launching our forces." The king asked, "What is it?" Sun Wu said, "Our southern neighbor, the state of Yue, has long coveted us. If, while we march north to attack Chu, they take advantage of our absence to launch a full-scale invasion, we would face enemies on two fronts and could be destroyed overnight." Cold sweat broke out on the king's spine as he exclaimed, "What should we do? What should we do?" Sun Wu said, "Send an envoy to Yue to gauge their intentions. Tell them we are preparing to attack Chu but lack sufficient troops and grain, and request they lend us soldiers and supplies. If Yue agrees to our request, they harbor no intention to attack us, and then we can confidently proceed against Chu." Wu Zixu asked, "What if Yue refuses?" Sun Wu replied, "Then they certainly plan to attack us from behind. Strike first to gain the advantage. Before attacking Chu, we must deal with Yue first."
A few days later, the Wu envoy arrived in Yue and personally presented King Helü's request for troops and grain. The king of Yue felt the matter was serious and consulted his civil and military officials. General Xu Shu said, "We must not lend them anything! Letting Wu use our men to die in their wars—what kind of logic is that?" Chancellor Fan Li told the king of Yue, "King Helü's request for troops and grain isn't genuine aid-seeking; it's actually a probe to see if we'll take advantage of his campaign against Chu to attack him unprepared." The king of Yue was startled and asked Fan Li, "How should we handle this?" Fan Li replied, "Send an envoy with a letter to King Helü, saying our state is poor and our forces weak, so we can only supply some grain. This way, King Helü will feel secure enough to attack Chu. Once he leaves Wu to campaign, we will surprise-attack from behind, seize his territory—this is the superior strategy!" The king of Yue considered for a moment, finding Fan Li's strategy sound, so he wrote a letter and dispatched 500 dan of grain to Wu.
Sun Wu read the king of Yue's letter and asked Wu Zixu for his opinion. Wu Zixu said, "Yue sending grain shows they have no intention to invade. Now I can confidently attack Chu." Sun Wu shook his head, saying, "This letter is a deception tactic by Fan Li. We must not underestimate him; he is skilled in political intrigue. Sending only grain without troops is a trap. He uses grain to pacify us, intending to send troops to attack once we leave our homeland for Chu." Wu Zixu said, "The Yue people are truly cunning. Why not just find an excuse to eliminate them?" Sun Wu waved his hand, saying, "They have treated us courteously and sent us grain. If we respond with violence, we will lose credibility across the land. We cannot do that. I have devised a plan: station 5,000 troops along the Wu-Yue border. Thus, when I attack Chu, Yue will not dare to invade." Wu Zixu asked, puzzled, "If Yue really attacks, what good are 5,000 men?" Sun Wu replied, "Fan Li is intelligent. Seeing our troops stationed on the border, he will realize his plot has been uncovered and will certainly not attack us."
Indeed, upon learning that Wu had stationed troops on its border, Fan Li sighed, "I sent 500 dan of grain hoping to deceive Wu, yet it was seen through. It seems Sun Wu truly lives up to his reputation—a master of strategy. Fighting such a man, who knows when we might fall victim to his schemes? Better not to invite trouble!"
With his rear secured, Sun Wu formally declared war and launched the campaign against Chu. Upon entering Chu territory, Wu won battle after battle, utterly defeating the Chu army, advancing all the way to Chu's capital. The king of Chu barely escaped, escorted by his bodyguards. The once-dominant king of Chu met a tragic end.
After the victory over Chu, King Helü credited Sun Wu with the primary achievement. However, Sun Wu had no desire for official office and retired to his hometown. He left behind a work known as *The Art of War*, a world-renowned masterpiece of military strategy.