At the time he took the throne, Chen had been devastated by war during the preceding Liang dynasty, and many provinces nominally loyal to him were under control of relatively independent warlords.

He quickly distinguished himself in minor campaigns against local bandits, and he became one of Chen Baxian's trusted generals.

When Chen Baxian succeeded surprisingly quickly, Du, along with Wei Zai (韋載) the governor of Yixing Commandery (義興, roughly modern Wuxi, Jiangsu), and Wang Sengzhi (王僧智, Wang Sengbian's brother) the governor of Wu Commandery (roughly modern Suzhou, Jiangsu) rose against Chen Baxian.

This allowed Chen Baxian to come to his aid, forcing Wei to surrender and Wang Sengzhi to flee to Du.

Chen Qian and Zhou were subsequently also able to take over Eastern Yang Province (東揚州, modern northeastern Zhejiang) from its governor Zhang Biao (張彪), who was loyal to Wang Sengbian.

Subsequently, a peace was negotiated with Wang, although border conflicts continued, and Chen Qian, by Emperor Wu's orders, constructed a fortress at Nanhuan (南皖, in modern Anqing, Anhui) to defend a potential Wang attack.

While Chen Qian was still at Nanhuan, in summer 559, Emperor Wu grew ill and quickly died.

Emperor Wu's wife Empress Zhang Yao'er, after consulting the officials Du Leng (杜稜) and Cai Jingli (蔡景歷), chose not to announce Emperor Wu's death and summoned Chen Qian back from Nanhuan.

He created his wife Princess Shen Miaorong empress and her son Chen Bozong crown prince.

Hearing that Emperor Wu had died, Wang Lin launched a major attack on Chen in winter 559.

Emperor Wen summoned Hou Andu, suggesting that perhaps he should yield the throne to Chen Chang and accept a princely title.

In fall 560, Chen forces under Hou Tian began to engage Northern Zhou and Western Liang forces in the modern Hunan region, which Western Liang had taken from Xiao Zhuang when he fled to Northern Qi.

Meanwhile, Emperor Wen began to consider the problem of local warlordism—which rendered the modern Jiangxi, Fujian, and large parts of Zhejiang under warlord control and only nominally submissive to him.

Emperor Wen sent Wu Mingche to attack Zhou Di and sent Hou Andu against another warlord, Liu Yi (留異), who controlled modern southern Zhejiang.

By summer 562, Hou had defeated Liu Yi, forcing him to flee to his son-in-law, Chen Baoying (陳寶應), who controlled modern Fujian.

Chen Baoying, Liu Yi, and Zhou Di regrouped together and resisted Emperor Wen's forces and prepared to counterattack.

Meanwhile, Emperor Wen had become increasingly angry and suspicious of Hou Andu's arrogance and protection of his officers' misdeeds.

By fall 565, Emperor Wen's general Cheng Lingxi (程靈洗) was able to defeat Zhou Di, who was subsequently betrayed by his own soldiers and killed.

Fearing that Crown Prince Bozong was weak in personality and unable to serve competently as emperor, he offered to pass the throne to Chen Xu.