Belligerents
Background
In 219, as Liu Bei took his royal title, Guan Yu rode the momentum north against Cao Ren at Fancheng. He marched with the Wu alliance already soured over Jing Province — and stripped even his rear-guard garrisons for the front. Lü Meng feigned illness and installed the unknown Lu Xun in his place, and Guan Yu relaxed.
Course
When autumn floods burst the Han River, Guan Yu’s navy drowned Yu Jin’s seven armies whole and executed the general Pang De — "his majesty shook the heartland," and Cao Cao debated moving the capital. But Cao Ren’s Fancheng held, and Xu Huang’s relief force smashed through the siege. Meanwhile Lü Meng’s soldiers rowed upriver disguised as merchants and took Jing Province’s signal towers without a sound. Word that their families were being treated kindly dissolved Guan Yu’s army without a battle; cornered at Maicheng, he was captured and put to death.
Outcome & impact
Shu lost Jing Province and Guan Yu in one stroke, and the two-pronged northern offensive at the heart of the grand plan died forever. The Sun–Liu alliance was shattered, and the grievance detonated two years later at Yiling. The hinge on which the whole saga’s fate turned.
History vs. the novelHistoryvsNovel
Hua Tuo scraping the poisoned bone is chronologically impossible fiction, as are the death scenes tied back to sparing Cao Cao at Huarong. Even the drowning of the seven armies is reframed by the novel as an engineered dam-break; the histories describe the exploitation of a natural flood.