the new emperor. The day after his coronation, Emperor Wu enfeoffed his uncle Sima Zhou as the Prince of Dongguan (東莞王) with a princedom comprising 10,600 taxable households. He also granted permission to all the princes to appoint the county prefects/chiefs in the counties in their princedoms. Sima Zhou tried to ask Emperor Wu to remove this privilege but the emperor refused. In 268, Emperor Wu appointed Sima Zhou as Right Supervisor of the Masters of Writing (尚書右僕射) and General Who Pacifies the Army (撫軍將軍). In the following year, he reassigned Sima Zhou to be Senior General Who Guards the East (鎮東大將軍) and granted him imperial authority to replace Wei Guan in supervising military affairs in Xu Province. During his tenure, Sima Zhou instilled good discipline among the troops and earned much respect from them. The military leaders in the Jin dynasty's rival state, Eastern Wu, were very wary of him. On 5 October 277, Emperor Wu heeded a suggestion by the minister Yang Yao (楊珧) and started reshuffling the various princes and their princedoms. As Sima Zhou was in Xu Province at the time, Emperor Wu enfeoffed him as the Prince of Langya (琅邪王) while at the same time allowing him to retain his original princedom in Dongguan; Sima Zhou's princedom thus comprised both the commanderies of Dongguan and Langya. In 279, Sima Zhou participated in the Jin dynasty's campaign against Eastern Wu and led thousands of troops to attack the Wu position at Tuzhong (塗中). In 280, Sun Hao, the last Wu emperor, surrendered to the Jin dynasty. China was thus reunified under the Jin dynasty's rule. As a reward for Sima Zhou's contributions during the campaign, Emperor Wu enfeoffed two of Sima Zhou's sons as village marquises, each with a marquisate comprising 3,000 taxable households, in addition to granting him 6,000 rolls of silk. Some months later, Sima Zhou was reassigned to supervise military affairs in Qing Province and was given an additional appointment as a Palace Attendant (侍中). He was subsequently promoted to General-in-Chief (大將軍) and allowed to set up his own administrative office. When Sima Zhou became critically ill in 283, Emperor Wu bestowed several gifts on his family and even sent officials to visit him and enquire about his condition. Sima Zhou eventually died that year at the age of 57 (by East Asian age reckoning). Emperor Wu honoured him with the posthumous title