After Emperor Wu of Jin, Sima Yan, ascended the throne, he set his sights on annexing the Wu kingdom. Following the advice of his advisor Yang Hu, he ordered Wang Jun to oversee the construction of warships, preparing for the invasion of Wu.
Upon receiving his orders, Wang Jun began constructing warships in Yizhou, Shu Commandery. These vessels were an astonishing 120 paces long and wide, capable of carrying over 2,000 men. On deck, wooden towers were erected with gates on all four sides, allowing chariots and horses to gallop across the ship. The prows were painted with images of strange beasts and mythical birds, said to ward off the river gods.
Wang Jun built ships on the upper Yangtze River; wood shavings drifted downstream. Wu Yan, the governor of Wu, retrieved them and reported to Sun Hao, the Wu ruler: "Jin seems to be preparing to attack Wu. We must reinforce Jianping's troops. If Jin cannot take Jianping, they will not dare cross the Yangtze." Sun Hao paid no attention, indulging in pleasure while ignoring the state's safety.
Seven years later, Wang Jun was ready to attack Wu, but the Jin court was divided—some argued against a hasty invasion. Anxious, Wang Jun petitioned the throne: "Sun Hao, the Wu ruler, is debauched and cruel; his people are seething with resentment. Now is the perfect time to strike. The ships I built are aging and rotting, and I am seventy—I may die any day. I beg Your Majesty not to miss this opportunity." General Du Yu also urged an early campaign. Emperor Wu of Jin finally made his decision, and in 279 AD, he launched over 200,000 troops across six land and naval routes to conquer Wu.
General Wang Jun led his fleet from Chengdu, sailing downstream along the Yangtze. To block the Jin advance, the Wu kingdom had stretched iron chains across the river at strategic points and hidden iron spikes over ten feet long underwater to pierce enemy ships. But the Jin forces were prepared: they built dozens of massive bamboo rafts that swept aside the obstacles. Wang Jun's fleet surged forward, capturing key Wu strongholds one after another until they reached the Three Hills near Jianye. Only then did Wu ruler Sun Hao panic, ordering General Zhang Xiang to lead ten thousand sailors in resistance. But when Zhang Xiang saw the Jin army's banners blotting out the sun and their overwhelming momentum, he was terrified and surrendered without a fight.
In 280 AD, the Jin general Wang Jun led 80,000 troops ashore into Stone City, and the Wu emperor Sun Hao surrendered, ending the division of the Three Kingdoms—Wei, Shu, and Wu.
When Emperor Wu of Jin ordered the conquest of Wu, he instructed General Wang Jun: "When attacking Jianping, follow the command of Grand Commander Du Yu; when attacking Jianye, follow the command of Grand General Wang Hun." After taking Jianping, Wang Jun pressed forward with the wind at his back, heading straight for Jianye. Wang Hun then summoned him to discuss military strategy north of the Yangtze, but Wang Jun, seeing his massive fleet racing downstream, refused to stop, replying, "My ships are swift as lightning—anchoring now would lose the advantage." He sailed directly to Jianye and claimed victory. Furious with jealousy, Wang Hun reported to the emperor, "Wang Jun defied your decree and refused my command!" Unaware of the truth, the emperor rebuked Wang Jun. In his defense, Wang Jun wrote, "From the start, my forces swept all before us. At Sanshan, Wang Hun was on the north bank, but with the wind in our sails, I had no chance to meet him. I believe serving a ruler means acting with utter loyalty, risking everything for the state, and adapting to circumstances. If it benefits the nation, I would lay down my life without hesitation—even if it means my own ruin."
Emperor Wu of Jin found Wang Jun's reasoning sound. Despite repeated demands from Wang Hun and others to punish Wang Rui, the emperor never agreed. Instead, he summoned Wang Rui to Luoyang and appointed him General of the Guard and Marquis of Xiangyang County.
The idiom "Suo Xiang Feng Mi" describes grass and trees bending with the wind, later used to mean fearing a strong enemy and fleeing in panic at the first sign.
Source: *Book of Jin*, "Biography of Wang Jun"
Meaning of the Idiom: Later, the Chinese idiom "所向风靡" came to describe grass and trees bending with the wind, later used to mean fearing a strong enemy and fleeing in panic at the first sign.