The Battle of Yehuling, literally the Battle of Wild Fox Ridge, was a major decisive battle fought between the Mongol Empire and Jurchen-led Jin dynasty during the first stage of the Mongol conquest of the Jin dynasty. The battle was fought between August and October 1211 at Yehuling (野狐嶺; lit. "Wild Fox Ridge"), which is located northwest of present-day Wanquan District, Zhangjiakou, Hebei Province. The battle, which concluded with a decisive Mongol victory, was followed by the assassination of the Jin emperor, Wanyan Yongji, by one of his generals. It also hastened the weakening and decline of the Jin dynasty.

In 1206, Temüjin had united all the tribes in Mongolia under his rule and received the title "Genghis Khan". The Jurchen-led Jin dynasty in northern China became a major obstacle to the Mongol Empire's quest for world domination. In the past, the Jin dynasty had adopted a divide-and-rule strategy to break up the various Mongol tribes and keep them under control. However, after realising that this strategy no longer worked, they began to actively prepare for war with the aim of eliminating the Mongol threat in a single campaign. Starting in the reign of Emperor Zhangzong, the Jin dynasty had constructed a line of structural defences about 300 kilometres long along its northern border; this line is sometimes loosely referred to as the "Jin dynasty's Great Wall".

Earlier in 1204, Genghis Khan had subdued the Ongud, a Mongol tribe helping the Jin dynasty guard its northern border. At the same time, Genghis Khan also formed an alliance with the Ongud by marrying his daughter to the Ongud chief's son. The Mongols controlled the area north of the Yin Mountains and started stockpiling resources in preparation for a military campaign against the Jin dynasty. Moreover, the Mongols had also been actively luring and inducing some Jurchens to defect or surrender. The Jin emperor, Wanyan Yongji, underestimated the Mongol threat and had been gradually neglecting the defences against the Mongols. He was also delusional in his belief that the Jin dynasty was far more powerful than the Mongols.

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