During the battles with Jin, Duke Mu heard that one of Duke Xian's exiled sons, Chong'er, was taking refuge in the Chu state. After consulting his subjects, Duke Mu sent an emissary to Chu to invite Chong'er over, and helped Chong'er defeat his brother Duke Hui and become the new ruler of Jin, with his title as "Duke Wen". Duke Wen was grateful to Duke Mu and relations between Qin and Jin improved. With his eastern front stable, Duke Mu used the opportunity to launch military campaigns against the minority tribes in the west.