后秦
As the years went by, Liu Yu gradually concentrated more and more power in his hands, destroying rivals including Liu Yi (), Zhuge Zhangmin (), and Sima Xiuzhi (), while greatly showing his strength in campaigns destroying rival states Southern Yan, Western Shu, and Later Qin. Sima Dewen continued to be largely ceremonially honored but actually powerless during this period. In 416, during Liu Yu's campaign against Later Qin, Sima Dewen asked to undertake a mission in Luoyang, recently captured from Later Qin, to try to restore the imperial tombs of the early Jin emperors, but it is not known what came of the mission. He returned to Jiankang in 418 after Liu Yu destroyed Later Qin.