After the fall of the Qin Dynasty in 206 BC, Xiang Yu, who had crushed the main Qin forces, declared himself Hegemon-King of Western Chu and enfeoffed Liu Bang as King of Han. This sparked a five-year-long Chu-Han War between the two rivals for control of the entire realm.
Taking advantage of Xiang Yu's campaign against Qi, Liu Bang seized Guanzhong and pressed eastward, capturing Xiang Yu's base at Pengcheng (modern Xuzhou, Jiangsu). But Xiang Yu, with superior military strength, turned back and routed Liu Bang's forces. Liu Bang then allied with other opponents of Xiang Yu, stalemating him, while sending Han Xin to conquer Qi and Zhao, forcing Xiang Yu to fight on two fronts.
In 202 BCE, Liu Bang seized the moment as Xiang Yu withdrew toward Pengcheng, launching a full pursuit and summoning Han Xin and others to encircle him. By year's end, Xiang Yu was trapped at Gaixia (southeast of present-day Lingbi County, Anhui Province), surrounded by Han forces on all sides.
By then, Xiang Yu's forces were dwindling and his food supplies exhausted, while Liu Bang's army was strong, well-provisioned, and had surrounded Xiang Yu's remaining troops in multiple layers.
Liu Bang employed psychological warfare, ordering his Han troops to sing songs of Chu, creating the impression among Chu forces that their homeland had been completely conquered, thereby shaking their morale.
One night, Xiang Yu heard Chu songs rising from all sides. Startled, he muttered to himself, "Could the Han army have already taken all of Chu? Why are there so many Chu people here?"
Xiang Yu, sensing that the tide had turned against him, was overwhelmed with despair. He ordered wine to be brought to his tent, hoping to drown his sorrows.
He had a beloved concubine named Yu Ji, who often stayed by his side; he also had a fine horse with a mix of green and white, called Zhui, which he frequently rode. Now trapped in a heavy siege, he thought of his beautiful concubine and famous horse, and could not help but drink while singing with sorrow and passion:
My strength can uproot mountains, my courage unmatched in all the world.
When fortune turns against you, even your finest steed refuses to move forward.
When the warhorse refuses to advance, what can be done?
Ah Yu, my Yu, how am I to settle you?
After singing it several times, Consort Yu joined him in the song. Xiang Yu's tears streamed down as he sang, and the attendants around him wept along, none able to lift their heads to witness the tragic scene.
That night, Xiang Yu led over 800 cavalrymen in a breakout, fleeing southward. The next morning, lost and unsure of the way, he asked a farmer for directions. The farmer, who deeply resented Xiang Yu, deliberately pointed him down the wrong path. Unaware of the deception, Xiang Yu ordered his men to follow the false route.
After traveling only a short distance, the remnants of Xiang Yu's army became mired in a swamp, their pace slowing to a crawl as Han troops closed in from behind. By the time Xiang Yu reached the Wu River, he had only twenty-eight cavalrymen left, while thousands of Han soldiers pursued him. With no escape route left, Xiang Yu drew his sword and took his own life.
Later generations, drawing from Xiang Yu's encirclement at Gaixia, coined the idiom "Ambushed on All Sides" to describe being trapped and isolated with no escape.
Source: *Records of the Grand Historian*, "Biography of Xiang Yu"
Meaning of the Idiom: Later, the Chinese idiom "四面楚歌" came to describe being trapped and isolated with no escape.