李存勗
In 921, Wang Rong, who had by that point become independent of Later Liang as the Prince of Zhao and was allied with Li Cunxu, was assassinated by his adoptive son Wang Deming, who then took over his domain and changed his name back to the birth name of Zhang Wenli. Li Cunxu, wanting to avenge Wang Rong, launched a campaign against Zhang. Zhang sought aid from the Khitan's Emperor Taizu (Yelü Abaoji), who quickly advanced into Jin's Lulong Circuit. Li Cunxu himself headed north to engage the Khitan emperor, but his army, terrified at the Khitan cavalry strength, had low morale, and Li Cunxu considered, pursuant to some officers' request, lifting the siege on Zhao's capital Zhen Prefecture () and withdrawing. Li Sizhao pointed out that doing so would merely cause the army to collapse. Li Cunxu therefore resolved to engage the Khitan army head-on, and defeated the Khitan army in a battle in which Li Sizhao led successful Jin cavalry maneuvers to save Li Cunxu when Li Cunxu was, at one point, surrounded by Khitan's Xi soldiers.