司馬穎
Sima Ying was Emperor Wu of Jin's 16th son, by his concubine Consort Cheng. In 289, Emperor Wu created him the Prince of Chengdu. After Emperor Wu died in 290 and Emperor Hui succeeded to the throne, Sima Ying remained in the capital Luoyang. However, after he once rebuked Jia Mi (), the nephew of Emperor Hui's powerful wife Empress Jia Nanfeng, for disrespecting Emperor Hui's son Sima Yu the crown prince, Empress Jia sent Sima Ying away from the capital to take up the defense post for the important city of Yecheng (鄴城, in modern Handan, Hebei). Sima Ying was handsome but not much more intelligent than his developmentally disabled brother Emperor Hui, but he developed a good reputation among officials and the people by being lenient, filial to his mother Princess Dowager Cheng, and listening to the advice of his capable advisor Lu Zhi ().