In July 361, Emperor Mu died without a son. Emperor Mu's mother
Empress Dowager Chu thus ordered that Sima Pi be made emperor, and he took the throne as Emperor Ai, at age 20. He created his wife Princess Consort Wang as
empress in October 361, and his brother Sima Yi, who previously carried the title the Prince of Donghai, as the Prince of Langya. Since he was an adult, Empress Dowager Chu did not serve as regent for him, and he honored his mother Consort Zhou as Consort Dowager () in 362, but with supplies and ceremonies similar to the empress dowager. However, the decision-making process was largely in the hands of the general
Huan Wen and Emperor Ai's granduncle
Sima Yu the Prince of Kuaiji. In 362, Huan, after securing the
Luoyang region, requested that the capital be moved back to Luoyang, where it had been until it had been captured by
Han Zhao in 311. The imperial government, under an edict issued by Emperor Ai, declined. In 363, Consort Dowager Zhou died. In accordance with proper protocol that he could no longer honor her as mother, out of respect for Empress Dowgaer Chu, Emperor Ai did not observe the normal mourning period due to a mother. Emperor Ai was obsessed with seeking immortality, and despite his young age, he died from
Chinese alchemical elixir poisoning. In 364, he became poisoned by pills given him by magicians, and he grew so ill that he was unable to handle important matters. Empress Dowager Chu had to resume
regency on his behalf. Later in 364,
Former Yan launched a major attack against Luoyang, and Huan and Sima Yu considered a counterattack to relieve Luoyang. However, as Emperor Ai died in March 365, that plan was cancelled, and Luoyang soon fell. As he did not have a son, Emperor Ai was succeeded by his brother Sima Yi, as Emperor Fei. Emperor Ai was preceded in death by his wife Empress Wang, who died about a month before he died; they were buried together with imperial honors. ==Era names==