In 204 BC, Sima Xin and Dong Yi joined Xiang Yu's subordinate Cao Jiu in fighting Liu Bang's forces during the Battle of Chenggao, but they were defeated and all three of them committed suicide.
When Xiang Liang was arrested after getting into trouble with the law, he asked Cao Jiu (曹咎), then serving as a prison officer in Qi County (蘄縣; present-day Suzhou, Anhui), to help him write to Sima Xin.
In 209 BC, the Dazexiang uprising broke out under the leadership of Chen Sheng and Wu Guang and sparked off a series of rebellions against the Qin dynasty throughout China.
The emperor approved Zhang Han's proposal and appointed him as a general, putting him in charge of leading Qin forces to fight the rebels.
The Qin forces under Zhang Han's command continued to advance eastward and destroyed Chen Sheng's rebel group.
When Zhang Han sent Sima Xin to request reinforcements from Xianyang, the emperor refused to send aid after being deceived by Zhao Gao.
The following year, Sima Xin and Dong Yi joined Cao Jiu (曹咎), who was serving under Xiang Yu, in resisting an attack by Liu Bang's forces during the Battle of Chenggao.