Sima Lun (traditional Chinese: 司馬倫; simplified Chinese: 司马伦; pinyin: Sīmǎ Lún; Wade–Giles: Ssu-ma Lun) (born before 250[6] – poisoned June 5, 301), courtesy nameZiyi (子彛), was titled the Prince of Zhao (趙王; 赵王; Zhào Wáng) and the usurper of the Jin Dynasty from February 3 to May 31, 301. He is usually not counted in the list of Jin emperors due to his brief reign, and was often mentioned by historians as an usurper. He was the third of the eight princes commonly associated with the War of the Eight Princes.
^Volume 84 of Zizhi Tongjian recorded that Sima Lun usurped the throne on the yichou day of the 1st month of the 1st year of the Yong'ning era. This corresponds to 3 Feb 301 in the Julian calendar.
^Volume 84 of Zizhi Tongjian recorded that Sima Lun died on the dingmao day of the 4th month of the 1st year of the Yongning era. This corresponds to 5 Jun 301 in the Julian calendar.
^Volume 84 of Zizhi Tongjian recorded that Sima Zhong was restored to the throne on the guihai day of the 4th month of the 1st year of the Yongning era. This corresponds to 1 June 301 in the Julian calendar.
^Historical records have very little to say on Lady Bai. She was a concubine of Sima Yi, and he doted on her to the extent of neglecting his main wife, Zhang Chunhua. (其后柏夫人有宠,后罕得进见。) Jin Shu, vol.31. She did not receive any title, even after her son Sima Lun became emperor. The Book of Jin also recorded a piece of advice Sima Gan (a full brother of Sima Shi and Sima Zhao) gave to Sima Jiong after Jiong became regent, that he "should not emulate Lady Bai". (冏既辅政,干诣之,冏出迎拜。干入,踞其床,不命冏坐,语之曰:“汝勿效白女儿。”其意指伦也。) Jin Shu, vol.38. The Jin Shu implied that Gan advised Jiong not to crown himself emperor, with Lun as the cautionary example.
^While Sima Lun's birth year was not recorded, he was younger than his half-brothers Sima Gan and Sima Jun, who were born in 232.