李希烈
It is not known when Li Xilie was born, but it is known that his family was from Yan Prefecture (燕州, in modern Siping, Jilin), and that his father's name was Dading (). His surname might have been originally Dong. It was said that he joined the army of Pinglu Circuit (平盧, then headquartered in modern Chaoyang, Liaoning). During the Anshi Rebellion, when part of the Pinglu army was led by Li Zhongchen — then still named Dong Qin and who might have been Li Xilie's father's cousin — across the Bohai Sea, to join the campaign against the rebel Yan state north of the Yellow River. Later, after Li Zhongchen was made the military governor ("Jiedushi") of Huaixi Circuit (淮西, headquartered in modern Zhumadian, Henan), Li Xilie followed him there and served under him.