This paper examines Jiang Yueguang’s Guo jiang qi shi to shed light on how Zhu Yousong, the Prince of Fu, was enthroned as the Hongguang Emperor. The evidence suggests that in Guo jiang qi shi, Shi Kefa was not deeply involved in the enthronement of the new emperor, but rather, was swayed by Ma Shiying, and that the eunuch Lu Jiude planned to have Zhu Yousong, the Prince of Fu, enthroned as emperor. Initially, Ma Shiying was not a member of the group that sought Zhu Yousong’s enthronement. Ma Shiying, however, changed his position after seeing Lu Jiude’s plan. These findings are significantly different from the understanding that has prevailed hitherto.