Zhou Dewei
The first historical reference to Ma was in 919, when he was then serving, alongside the officer Meng Zhixiang (the husband of Li Cunxu's elder sister), as a chief of staff (中門使, "Zhongmenshi") for Li Cunxu, who was then the Prince of Jin, in Li Cunxu's capacity as the military governor ("Jiedushi") of Hedong (河東, headquartered in modern Taiyuan, Shanxi) and Tianxiong (天雄, headquartered in modern Handan, Hebei) Circuits. In 918, Li Cunxu's highly regarded general Zhou Dewei the military governor of Lulong Circuit (盧龍, headquartered in modern Beijing) had been killed in battle on Li Cunxu's campaign against Jin's archrival Later Liang. In 919, Li Cunxu briefly replaced Zhou with his cousin Li Sizhao, but soon thereafter, apparently believing that it was ill-advised to send Li Sizhao far away from his own Zhaoyi Circuit (昭義, headquartered in modern Changzhi, Shanxi), Li Cunxu personally assumed the command of Lulong, but sent Li Shaohong to Lulong to oversee the circuit in Li Sizhao's place. (Shortly after Li Shaohong's departure for Lulong, Meng resigned from the position of chief of staff, leaving Li Shaohong's and Meng's deputy Guo Chongtao as the new chief of staff.) In 921, when Khitan Empire's Emperor Taizu invaded Jin to assist the Chengde Circuit (成德, headquartered in modern Shijiazhuang, Hebei) rebels led by Zhang Chujin, it was Li Shaohong who defended Lulong's capital You Prefecture (幽州) against the Khitan attack.