Battle of Fei River
The first reference to Murong Long in history was in 369, when Murong Chui, then a Former Yan prince, fled to Former Qin after he came after suspicion of the emperor Murong Wei's mother Empress Dowager Kezuhun and the regent Murong Ping; Murong Long was one of his sons who fled with him. When Murong Chui subsequently resolved to rebel against Former Qin after its emperor Fu Jiān was defeated at the Battle of Fei River in his attempt to conquer Jin and reunite China, Murong Long was involved in his first act of rebellion — massacring the Di soldiers that Murong Chui's deputy, Fu Feilong (苻飛龍), commanded. Murong Chui subsequently declared the independence of Later Yan in 384.