He was most known for leading the empire's restoration movement against the state of Han-Zhao in Anding (安定, present-day Zhenyuan, Gansu) following the Disaster of Yongjia in 311.
However, his untimely death in January 313 undermined the potential of the group, as power would fall into the hands of Suo Chen and Qu Yun, who held on desperately to their influence on Emperor Min of Jin in Chang'an.
However, they did not reach the capital, rather they were led home by Sima Mo's subordinates Suo Chen and Qu Yun, who were fleeing from Han forces.
Jia Ya's success convinced many in the Guanxi (關西, west of Hangu Pass) region to surrender to him as well, returning it under Jin control.
[7] Sima Ye was proclaimed as the new Crown Prince in Chang'an and Jia Ya was appointed as Grand General Who Conquers The West.
[8] The new regime that Jia Ya had found continued to survive under the guidance of Suo Chen and Qu Yun, but eventually perished in 316 when Sima Ye, posthumously known as Emperor Min of Jin, surrendered to besieging Han forces.