Among ancient Chinese military strategists, Han Xin was a master of idioms—one man who contributed a remarkable number of them to the language. "Fighting with one's back to the river" (背水一战, bèishuǐ yīzhàn) is one of the most famous. It refers to the Battle of Jingxing, in which Han Xin, facing the Zhao army, deployed his troops with their backs to the water and ultimately defeated the enemy. Today, the idiom is mainly used to describe the determination of staking everything on a single throw. But in terms of capturing the essence of the Battle of Jingxing, I don't think it's a very good idiom. "Back to the river" fails to convey Han Xin's command artistry and dialectical mastery of warfare in this campaign.
The battle is recorded in the Records of the Grand Historian and the Book of Han. The latter provides a more detailed account:
Han Xin and Zhang Er, with an army of tens of thousands, intended to march east through Jingxing Pass to attack Zhao. The King of Zhao and his general Chen Yu, Lord of Cheng'an, upon hearing that the Han army was coming, gathered their forces at the mouth of Jingxing Pass, claiming to number two hundred thousand. The strategist Li Zuoche counseled Chen Yu: "I have heard that the Han general Han Xin crossed the West River, captured the King of Wei, took Xia Yue prisoner, and recently shed blood at Eyu. Now, supported by Zhang Er, he plans to take Zhao. He rides the momentum of consecutive victories, fighting far from home—his edge cannot be blunted. Yet I've heard it said: 'When supplies must travel a thousand li, the soldiers wear a look of hunger; when they must gather firewood before cooking, the army never eats its fill.' The road through Jingxing is so narrow that chariots cannot ride abreast nor cavalry form ranks, and the march stretches hundreds of li—their supplies must lag behind. Grant me thirty thousand crack troops, and I will take a hidden path to cut off their baggage train. You, my lord, dig deep trenches and raise high ramparts and refuse battle. They will not be able to fight ahead or retreat behind; my forces will cut off their rear; they will find nothing to forage in the wild. Within ten days, the heads of both their generals can be laid at your feet. Please consider my plan—if you do not, you will surely be captured by them."
But Chen Yu, a Confucian scholar, often proclaimed that a righteous army does not employ deception. He said: "The Art of War says: 'When you outnumber the enemy ten to one, surround them; when two to one, engage.' Han Xin's army is said to number tens of thousands, but in reality it cannot be so many. Having marched a thousand li to attack us, they must be exhausted. If we avoid engaging such a force now, what will we do when a larger one comes? The other lords will call us cowards and attack us at will." He rejected Li Zuoche's strategy.
When Han Xin's spy reported that the plan had been rejected, Han Xin was overjoyed and dared then to advance his forces. He halted thirty li from the mouth of Jingxing Pass and made camp. At midnight he issued orders. He selected two thousand light cavalry, each carrying a red banner, and sent them via a hidden path to observe the Zhao camp from the mountains, warning them: "When the Zhao forces see us flee, they will empty their camp to pursue. Rush in at once, pull down the Zhao banners, and raise the Han banners." He instructed his junior officers to distribute a light meal, saying: "Today we break Zhao and feast together." The officers all smirked in disbelief and gave hollow assent: "Yes, sir." Han Xin told his staff: "Zhao has already occupied the advantageous ground and fortified it. Moreover, they have not yet seen our commander's banners and drums—they will not attack our vanguard, fearing we might turn back at the pass." He then sent ten thousand men ahead to exit the pass and form a line with their backs to the river. The Zhao troops saw this and laughed derisively. At dawn, Han Xin raised the great commander's banners and drums and marched out of Jingxing Pass. Zhao opened its gates and attacked. A fierce battle raged for some time. Then Han Xin and Zhang Er abandoned their banners and drums and fled toward the river formation. The soldiers fought fiercely once more. Zhao emptied its camp to chase the Han banners and drums, pursuing Han Xin and Zhang Er. Once Han Xin and Zhang Er entered the riverside formation, every soldier fought desperately, and the Zhao army could not break them. The two thousand cavalry Han Xin had sent earlier watched for the Zhao camp to empty as the troops pursued. They galloped in, tore down every Zhao banner, and raised two thousand red Han banners. When the Zhao troops, unable to capture Han Xin and Zhang Er, tried to return to their camp, they found it filled with Han banners. Panic-stricken, believing the Han army had already captured the Zhao king and his generals, they broke and fled. Though Zhao officers beheaded deserters, they could not restore order. The Han forces attacked from both sides, crushing the Zhao army. Chen Yu was slain by the riverbank and the King of Zhao was captured. Han Xin then ordered that no one should harm Li Zuoche, and offered a thousand gold pieces for his capture alive. Shortly after, Li Zuoche was brought before him. Han Xin personally untied his bonds, seated him facing east in the position of honor, and treated him as his teacher.
The first section is the pre-battle background: Li Zuoche offers his plan; Chen Yu rejects it. Li Zuoche's ability later won Han Xin's respect, and he became an important advisor. Chen Yu, meanwhile, was reduced to a byword for the "benevolence of a woman" in the mold of Duke Xiang of Song. But upon reflection, Chen Yu's decision wasn't entirely without merit. The Zhao army claimed 200,000 troops and the Han army numbered in the tens of thousands—both sides likely exaggerated, but the Zhao forces were certainly several times larger. Zhao's army was massed at Jingxing Pass, a natural stronghold in the Taihang Mountains. The pre-battle situation for Zhao was a textbook case of resting versus exhausted, many versus few, with total initiative. Though the broader strategic situation is debated, the Han army's long-distance raid meant that upon reaching Jingxing Pass, they needed a quick decisive engagement—their supply line was already long and fragile (which is exactly why Han Xin was so alarmed by Li Zuoche's plan). If you were the Zhao commander, wouldn't you prefer to sit still rather than act? Holding the pass, standing in an unassailable position—what was wrong with that? Sending a detachment to ambush the supply train of a general like Han Xin also carried considerable risk.
Chen Yu appeared so weak not because he was truly incompetent, but because he faced Han Xin. Far tougher opponents—the fearsome Zhang Han and the mighty Long Ju—were just as easily dispatched by Han Xin.
The second section begins with: "When Han Xin's spy reported that the plan had been rejected." Consider how terrifying this is. Throughout his career, Han Xin won every battle and never failed a siege, and in every engagement he employed stratagems that worked perfectly. This was clearly more than just superior planning—Han Xin's intelligence apparatus was formidable. The line "was overjoyed" is likely literary embellishment rather than historical fact. Even if Li Zuoche had sent a detachment to raid Han Xin's supply train, it could not have prevented the Han army from storming Jingxing Pass. This was a do-or-die assault—they had no intention of relying on supply lines for a prolonged campaign.
Then comes the heart of the Battle of Jingxing. The Han army camped thirty li from the pass, and the next day's formation was likely deployed in this area. Before the "back to the river" deployment, Han Xin made two arrangements: first, he sent 2,000 cavalry to hide in the mountains, ready to seize the Zhao camp and swap the banners once the Zhao troops emptied their fortifications in pursuit. Han Xin himself then led a contingent to challenge the enemy at dawn. Before departing, he delivered an epic boast: "Today we break Zhao and feast together"—putting to shame even the Americans' "home by Thanksgiving" in the Korean War, and with a decidedly different outcome.
Han Xin marched out at dawn to engage, fought fiercely for a time, then feigned defeat—going all in on the act by abandoning his banners and war drums. In ancient warfare, command and control depended entirely on banners and drums; losing them meant the collapse of the command structure. No wonder the Zhao army was convinced. They chased Han Xin dozens of li all the way to the river. The Han forces deployed with their backs to the water let Han Xin's retreating troops through their lines and then engaged the Zhao army. At this point, the Han army had already achieved an unassailable position. Why? Because the Zhao army had just sprinted dozens of li in pursuit and now faced a fresh, well-rested Han formation. Though the historical record doesn't describe the river terrain in detail, some modern research suggests the formation sat at the confluence of two rivers, an angular piece of ground where the Han army deployed at the apex. This controlled the contact surface—the Zhao army's numerical advantage was neutralized, and the Han army had no need to worry about their flanks or rear (water on all sides).
Through his brilliant design, Han Xin lured the Zhao army onto a battlefield of his own choosing and successfully reversed the dynamics of numbers and fatigue. No matter what, the Zhao army was never going to win that morning. They'd run dozens of li, probably skipped breakfast, fought for a while without breaking through, and then turned to head back for lunch—only to discover their camp flying Han banners. At that moment, the riverside Han force surged forward from behind. Caught between two forces, the Zhao army collapsed.
As we can see, this battle was not won through the resolve and courage of fighting with one's back to the river. Through thorough reconnaissance and meticulous planning, Han Xin seized complete initiative over the battlefield. By the time of the riverside engagement, he already held the dominant position and stood in an unassailable situation. Those who see only the one trick of "place them in mortal ground and they will survive" without understanding the rest—few of them have survived to tell the tale. Not long after, the celebrated general Long Ju tried the same "back to the river" tactic against Han Xin and suffered total annihilation.
In fact, Han Xin had demonstrated this same dialectical mastery of warfare from the very start of his career. We all know the story of "repairing the plank road openly while secretly crossing through Chencang." The Han army seized Chencang by surprise—but that wasn't the end of it. Everyone said they should immediately attack Zhang Han. But Han Xin not only refused to attack—he made camp and waited for Zhang Han to come to him, defeating the enemy in a single engagement to pacify the Three Qin regions. In warfare, attacking is harder than defending, the tired lose to the rested, and the few lose to the many. The Han army had marched far into the Guanzhong region; they were the expeditionary force. Yet under special conditions, they transformed into the home force (aided of course by Han's political campaign), sat comfortably behind walls eating well, waited at ease for the exhausted Zhang Han to come crashing against them, and dispatched him with ease—securing the Guanzhong base that laid the foundation for the Han dynasty's unification of China.
Such was Han Xin's transcendent art of war. In terms of war record, perhaps a handful of commanders in history could contest the title of greatest (such as Li Shimin), but in terms of the artistry of warfare and the sheer output of idioms coined, Han Xin is unmatched, before or since.
BTW: Though it isn't the main theme of this essay, it must be said that Han Xin's strategic brilliance rested on a foundation of overwhelmingly superior operational competence (as Han Xin himself said: "The more troops I command, the better"). For instance, in the Battle of Jingxing, when Han Xin feigned defeat and abandoned his banners, over ten thousand men retreated in order, fell back to the riverbank, and were admitted into the formation without disrupting the lines. This kind of hard skill is the prerequisite for any stratagem. A lesser commander might have been trampled to death by his own panicking soldiers during the retreat.