The Battle of Kunyang (昆陽之戰), which took place between June and July of A.D. 23, pitted the Lulin troops against those of the Xin Dynasty. The Lulin forces were commanded by Liu Xiu, who would later become Han Emperor Guang Wudi, while the much larger Xin troops were under the command of Wang Yi and Wang Xun (王尋). Wang Xun is killed while launching a senseless attack against Liu”s forces with a small contingent of his soldiers. The Lulin soldiers disrupt the rest of the Xin army, forcing Wang Yi to withdraw. This decisive battle led to the fall of the Xin dynasty.
At the end of the Xin dynasty, peasant rebellions broke out all over the country. They were all aimed at Wang Mang, the founder and sole emperor of the Xin dynasty, who had proved incompetent during his years of rule. Calls for the restoration of the Han dynasty, overthrown by Wang Mang, were growing. Listening to these calls, the leaders of the Lulin rebellion proposed Liu Xuan to become the emperor of the new Han dynasty.
Wang Mang decided to crush this new Han dynasty before it could grow. To carry out this mission, he sent his cousin Wang Yi and his Prime Minister Wang Xun to attack the Lulin, with a powerful army of several hundred thousand men. To resist such a deployment of power, the troops of the Lulin are divided into two :
Wang Feng, Wang Chang and Liu Xiu quickly seize the castles of Kunyang (昆陽), Dingling (定陵) and Yanxian (郾縣). Meanwhile, Liu Xiu began to attack Yangguan (關), but after learning of the arrival of the bulk of the Xin troops, he decided to retreat to Kunyang. The 9,000 Lulin soldiers in Kunyang, greatly outnumbered by the Xin, initially wanted to disperse and retreat to Jingzhou, but Liu Xiu objected. He advocated staying in Kunyang where the soldiers would be safer, as a dispersed army would be easy prey. Liu Xiu promised to gather all other available troops in the surrounding areas and attack the Xin forces from outside the city. After initially rejecting Liu Xiu”s idea, the rebel soldiers eventually agree.
As the Xin forces approached Kunyang from the north, Liu Xiu took advantage of the night to ride out of the city with 13 horsemen in order to get reinforcements from Dingling and Yanxian.
Wang Yi, the commander of the Xin army, betting everything on his enormous numbers, declares that his army will “annihilate everything in its path, massacre (the inhabitants of) the city and dance in (their) blood. He immediately began to lay siege to the city. Faced with siege towers and tunnels dug under the castle walls, the defenders of Kunyang resisted until the return of Liu Xiu, who arrived on July 7 with 10,000 infantrymen and horsemen. At this point, the morale of the Xin troops fell, while that of the Lulin soldiers rose with Liu”s return. Liu took the opportunity to bring 1,000 men to attack the Xin, while another brigade of 3,000 troops moved to the rear of the Xin to attack their main camp. Wang Yi, who continued to underestimate the Lulin, personally took command of 10,000 men and left with Wang Xun to attack the enemy, while ordering the rest of his troops to remain in their positions unless he ordered them to attack. However, once engaged in the battle, and seeing that Yi suffered slight losses, the other units were reluctant to help them and finally Liu Xiu killed Wang Xun in battle. After Xun”s death, the Lulin soldiers inside Kunyang all leave the city and attack the other Xin units. Despite its much larger numbers, the Xin army collapses and its troops are routed. Adding to the misery of the Xin forces was a sudden storm that caused an equally sudden flood, which caused many fleeing men to drown.
Unable to gather most of his men, Wang Yi had to withdraw with the few thousand soldiers he had left to return to Luoyang. As soon as the news of the battle of Kunyang spread throughout the empire, popular uprisings multiplied in the four corners of the empire, the leaders of these revolts often ending up killing the representatives of the local government and presenting themselves as representatives of the new Han regime. Within a month, almost the whole of China escaped the control of the Xin dynasty, which finally collapsed on October 6, 23, when Wang Man was killed in his palace in Chang”an.
Finally, after many years of civil war, Liu Xiu eliminates one by one his rivals and reunifies China under the authority of Eastern Han.