Duke Xian of Jin
During the early reign of Duke Mu of Qin, the Jin state was a formidable power under the leadership of Duke Xian of Jin. However, after the death of Duke Xian, Jin plunged into a state of internal conflict as Duke Xian's sons fought over the succession. One of them won the contention and became Duke Hui of Jin, but Jin was struck by a famine not long later and Duke Hui requested aid from Qin. Duke Mu of Qin sent relief food supplies and agricultural equipment to Jin. However, Qin was struck by famine later and by then, Jin had recovered and it turned to attack Qin. Qin and Jin engaged in several battles over the next few years.