During the Three Kingdoms period, Wei and Shu fought for control of Hanzhong. After losing the fierce general Xiahou Yuan at Mount Dingjun, a furious Cao Cao personally led his army to the Han River. He ordered his general Zhang He to transport grain supplies to the northern mountain camp, then prepare to advance.
During the Shu Han period, Chancellor Zhuge Liang dispatched veteran generals Huang Zhong and Zhao Yun to battle. Huang Zhong and Zhao Yun agreed that Huang Zhong would seize the enemy's grain supplies the next day, and they arranged that if he did not return by a set time, Zhao Yun would lead reinforcements to his aid.
The next day, Zhang He was transporting a large supply of grain past Beixia Gate when Huang Zhong led his troops to intercept, sparking a fierce skirmish. Cao Cao sent reinforcements, trapping Huang Zhong between two forces with no escape. Zhao Yun, waiting long for Huang Zhong's return, took a few dozen cavalrymen out of camp to scout.
On the road, Zhao Yun happened to encounter Cao Cao leading his massive army on the attack, so Zhao Yun charged forward and engaged them in battle. The Cao forces gathered in greater numbers, but Zhao Yun and his men fought fiercely, breaking through the encirclement and returning to their camp.
Cao Cao's army charged fiercely, heading straight for the Shu camp
"Back then at the Battle of Changban Slope, I faced Cao Cao's thousands of troops alone on horseback without fear; now with soldiers and generals, what is there to fear from him!" With that, he first ordered some soldiers to ambush in the trenches outside the camp, then commanded the troops to "lower the banners and muffle the drums," while he himself stood alone on horseback at the camp gate to face the enemy.
When Cao Cao's forces arrived, they found the Shu camp eerily silent, with Zhao Yun standing alone before it, spear in hand, radiating a fierce, murderous aura. Fearing an ambush, Cao Cao immediately ordered a retreat. Seizing the moment, Zhao Yun led his hidden troops in pursuit. In the dim twilight, the Cao army, uncertain of the enemy's strength, panicked and fell into disarray. Zhao Yun and Huang Zhong pressed the attack, routing Cao's forces and capturing their supplies.
The next day, Liu Bei personally visited the military camp to reward his troops. After inspecting yesterday's battlefield, he praised, "Zilong (Zhao Yun's courtesy name) is truly all courage." Later, people used the idiom "lower the banners and silence the drums" to metaphorically describe a ceasefire or silently ceasing action.
Source: *Records of the Three Kingdoms*, Book of Shu, "Biography of Zhao Yun"
Meaning of the Idiom: Later, the Chinese idiom "偃旗息鼓" came to describe a ceasefire or silently ceasing action.