In 246 BC, when King Zhuangxiang died after a short reign of just three years, he was succeeded on the throne by his 13-year-old son. At the time, Zhao Zheng was still young, so Lü Buwei acted as the regent prime minister of the State of Qin, which was still waging war against the other six states. Nine years later, in 235 BC, Zhao Zheng assumed full power after Lü Buwei was banished for his involvement in a scandal with Queen Dowager Zhao. Zhao Chengjiao, the Lord Chang'an (长安君), was Zhao Zheng's legitimate half-brother, by the same father but from a different mother. After Zhao Zheng inherited the throne, Chengjiao rebelled at Tunliu and surrendered to the state of Zhao. Chengjiao's remaining retainers and families were executed by Zhao Zheng.