In 206 BC, following the collapse of the once-mighty Qin Empire, Chinese history entered a new phase. At that time, Xiang Yu, the Hegemon-King of Western Chu, and Liu Bang, the King of Han, formed two rival factions, sparking the famous Chu-Han Contention for control of the empire. Throughout this nearly five-year-long war, the Han general Han Xin demonstrated exceptional strategic brilliance and military acumen, fulfilling the ideal of "commanding a million troops from the command tent, winning every battle and capturing every objective."
In October of the third year of Emperor Gaozu of Han (204 BC), Han Xin led over ten thousand newly recruited Han troops across the Taihang Mountains, advancing eastward to attack the State of Zhao, a vassal of Xiang Yu. Zhao King Xi and Zhao's commander, Cheng'an Jun Chen Yu, concentrated 200,000 troops at Jingxing Pass (present-day Jingxing County, Hebei), a strategic mountain pass in the Taihang range. They occupied the high ground, preparing for a decisive battle against Han Xin. Jingxing Pass was one of the eight major passes through the Taihang Mountains. To its west lay a narrow, hundred-mile-long mountain trail—easy to defend, difficult to attack, and unsuitable for large-scale troop movements. The Zhao forces had already seized the pass, holding a commanding position with well-rested troops and superior numbers, thus enjoying both the strategic advantage and the initiative. In contrast, Han Xin commanded only over ten thousand men, mostly fresh recruits, who had marched a thousand li and were exhausted, placing them at a clear disadvantage and in a passive position.
Zhao strategist Li Zuoche advised Chen Yu: "We should hold our main position firmly and avoid direct battle, while sending a detachment to circle behind the enemy and cut off Han Xin’s supply lines. This will leave Han Xin unable to advance or retreat, with no resources to forage in the wild. Then, we can launch a coordinated attack from both front and rear, capturing Han Xin in a single stroke." However, Chen Yu was a traditionalist commander who valued direct confrontation. He rigidly adhered to the doctrine that "righteous armies need not resort to deceit or unusual tactics," and believed Han Xin’s small, weary force should not be avoided. He rejected Li Zuoche’s advice and mechanically followed the military maxim: "Surround if you outnumber ten to one; fight if you have double the enemy."
Han Xin, a deep and far-sighted strategist, knew full well that a direct assault against such overwhelming odds would lead to defeat. He therefore chose to camp far from Jingxing Pass and spent time carefully studying the terrain and Zhao deployments. Upon learning that Li Zuoche’s plan had been rejected and that Chen Yu was overconfident and eager for a quick victory, Han Xin immediately ordered his army to advance to a camp just thirty li from Jingxing Pass. That night, he selected 2,000 light cavalry, each carrying a red Han banner, and under cover of darkness, they secretly took mountain trails to hide behind the Zhao camp. Their mission: when the Zhao army moved out the next day, leaving their camp empty, they would rush in, replace the Zhao banners with Han flags, and seize the camp.
Han Xin then ordered his troops to eat, telling his officers: "Eat lightly now; after we defeat Zhao at dawn, we will feast properly." The officers were skeptical but obeyed. Han Xin then ordered drums to sound and the general’s banners to be raised, marching toward Jingxing Pass. He explained: "The Zhao army has already occupied the advantageous position and awaits us behind fortifications. If they don’t see my commander’s insignia, they may suspect my main force is still in the rear and hesitate to attack."
As the Han army approached Jingxing Pass, Han Xin sent no cavalry scouts and immediately ordered his main force to advance and form a battle line with their backs to a river. From their fortifications, the Zhao troops saw the Han army arrayed with no escape route and mocked Han Xin for not understanding military tactics. Shortly after, as dawn broke, a cloud of dust rose from the Han camp. To the beat of urgent drums, the general’s banners emerged, and Han Xin, surrounded by his officers, rode forward to the front lines. Seeing Han Xin’s small force and confident in their superior position, Chen Yu led his elite cavalry in a furious charge, hoping to capture Han Xin alive. Han Xin ordered his troops to discard their banners and drums and quickly retreat into their formation. Seeing this, Chen Yu immediately ordered a full-scale assault on the Han lines.
With the river at their backs, the Han soldiers knew retreat was impossible and fought with desperate courage, each man pressing forward. The two armies fought fiercely for over half a day, yet the Zhao army could not gain the upper hand. By then, the Zhao camp was empty. Han Xin’s 2,000 hidden cavalry charged in, replacing every Zhao banner with a Han red flag. The Zhao troops, locked in fierce combat, suddenly saw their own camp filled with Han banners. Panic erupted, and their formation collapsed. Seizing the moment, Han Xin launched a full counterattack, utterly routing the 200,000-strong Zhao army. Chen Yu was killed in battle, and King Xi of Zhao was captured.
After the battle, Han troops celebrated with feasting and wine. Many asked Han Xin: "General, you ordered us to form a battle line with our backs to the river—a direct violation of military doctrine. How could we possibly win?" Han Xin laughed heartily: "Didn’t the military classics say, 'Place your army in a desperate position and they will survive; place them in a deadly situation and they will live'? If I had given them a way to escape, would they have fought to the death?" The officers finally understood the profound wisdom behind the "back-to-the-river" formation and were deeply awed by Han Xin’s genius.
At the Battle of Jingxing, Han Xin, with only over ten thousand exhausted troops at a severe disadvantage, employed both orthodox and unorthodox tactics, formed a "back-to-the-river" battle line, and used flexible strategies to decisively crush 200,000 Zhao troops. He destroyed the Zhao state, a fiefdom established by Xiang Yu, and wrote a brilliant chapter in Chinese military history. The Tang Dynasty poet Wang Wei vividly described this great battle in his poem "On Military Service," praising Han Xin’s superb strategy and command: "Long have I worn armor in service; the shifting winds and clouds make formations hard to discern. Today we honor Han Xin—Cheng'an’s head shall fall within days."