Overview
Dong Yi (died 204 BC) was a military general of the Qin dynasty. He surrendered to Xiang Yu after the Battle of Julu in 207 BC. In 206 BC, following the collapse of the Qin dynasty, he was conferred the title of "King of Di" (翟王) by Xiang Yu and given part of the lands in Guanzhong as his fief when the latter split the former Qin Empire into the Eighteen Kingdoms.
Life
Dong Yi was a descendant of Dong Hu (董狐), a high ranking minister in the Jin state during the Spring and Autumn period.
In 209 BC, Chen Sheng and Wu Guang started the Dazexiang Uprising to overthrow the Qin Dynasty. The Qin emperor, Qin Er Shi, placed Zhang Han in command of the imperial army, with Sima Xin and Dong Yi serving as his deputies, to quell the rebels.
In 207 BC, Zhang Han attacked the insurgent Zhao kingdom and besieged Zhao forces at Julu. Xiang Yu of the Chu kingdom came to Zhao's aid and defeated the Qin army at the Battle of Julu, despite having a smaller force. Zhang Han sent Sima Xin to the capital Xianyang to request for reinforcements. Sima Xin later reported to Zhang Han that reinforcements would not be arriving, and that the state power of Qin had fallen into the hands of Zhao Gao. Zhang Han was aware that even if he defeated the rebels, Zhao Gao would later frame him for treason and have him executed, hence he decided to surrender to Xiang Yu. Xiang Yu accepted the surrender.
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