Meanwhile, as the Tang generals began to gather their forces to force Huang Chao out of Chang'an, Zhao Chou began to anticipate the likelihood that Huang, who had by that point claimed the title of Emperor of Qi but who was suffering defeats at Tang generals' hands, would abandon Chang'an and head east, particularly since Huang bore particular resentment to Zhongwu Circuit due to the prior engagements that he had with the Zhongwu army. In preparation, he repaired the city walls and stored excess food supplies, and ordered the people living within 60
li (about 30 kilometers) to move into the city. He divided his soldiers and had his brothers Zhao Chang () and Zhao Xu (), as well as his sons Zhao Lu () and
Zhao Lin command them. In spring 883, Huang, under the pressure of the Tang general
Li Keyong, abandoned Chang'an and fled east. He initially attacked Tang's Fengguo Circuit (奉國, headquartered at Cai Prefecture (), also in modern Zhumadian); the military governor of Fengguo Circuit,
Qin Zongquan, submitted to Huang and joined his forces to Huang's. Huang then sent his general Meng Kai () to attack Chen Prefecture. Zhao Chou initially feigned weakness to draw Meng in, and then ambushed Meng, killing him. Huang, angry over Meng's death, put Chen under siege for months, but could not capture it, and during the siege, Zhao made repeated surprise attacks against Huang's army. He also sought aid from the nearby military governors; among those,
Zhou Ji the military governor of Zhongwu,
Shi Pu the military governor of Ganhua Circuit (感化, headquartered in modern
Xuzhou,
Jiangsu), and
Zhu Quanzhong the military governor of Xuanwu all sent aid. However, they were all unable to lift the siege that Huang's army was putting on Chen. Fearing the strength of Huang's army, they sought aid from Li Keyong, who had by then been made the military governor of Hedong Circuit (河東, headquartered in modern
Taiyuan,
Shanxi). Li Keyong crossed the
Yellow River south and engaged Huang's army. Fearing Li Keyong's strength, Huang lifted the siege on Chen after some 300 days, in summer 884. == Defense of Chen Prefecture against Qin Zongquan ==