Gao Pian
It is not known when Lei Man was born, but it is known that he was of non-Han extraction, whose people lived in caves in the Wuling (武陵, in modern Changde, Hunan) region, in Lang Prefecture. During the time when the Tang general Gao Pian served as the military governor of Jingnan Circuit (荊南, headquartered in modern Jingzhou, Hubei), which Lang Prefecture belonged to then, Lei became an officer under Gao, commanding non-Han soldiers of the region. As Gao was later transferred to Zhenhai Circuit (鎮海, headquartered in modern Zhenjiang, Jiangsu), and then Huainan Circuit (淮南, headquartered in modern Yangzhou, Jiangsu), Lei followed him to those circuits along with his non-Han soldiers.