背水一战

Origin and story

In Shiji (史记), volume 92, Han Xin fights Zhao at Jingxing. He positions ten thousand men with their backs to the water, provoking the enemy's laughter. But this is only part of his plan. Two thousand concealed cavalrymen have orders to enter the Zhao camp once its defenders pursue him, remove its banners, and raise Han's red flags.

Han Xin and Zhang Er feign retreat toward the riverside troops, who stand and fight. Meanwhile the cavalry seize the emptied camp. Seeing unfamiliar banners when they try to return, the Zhao forces panic, and Han's coordinated attacks defeat them. The idiom focuses on fighting with no easy retreat, but the account combines determination with deception and preparation. An earlier discussion of a back-to-water formation in Weiliaozi (尉缭子), Tian Guan, likewise stresses human factors rather than the supposedly automatic power of a formation.