Complex sentence: It is evident that the Qing army at first met strenuous resistance at Devanchi and the forcing of the Tian Shan defiles had not been accomplished when news reached the garrison that their ruler had been expelled from Turfan by a fresh Qing army.
Split into simpler sentences: It is evident that the Qing army at first met strenuous resistance at Devanchi. The forcing of the Tian Shan defiles had not been accomplished when news reached the garrison that their ruler had been expelled from Turfan by a fresh Qing army.