, ▁Pe i ▁was ▁appointed ▁the ▁general ▁of ▁An xi ▁Prote ctor ate . ▁After ▁serving ▁in ▁An xi ▁for ▁several ▁years , ▁he ▁returned ▁to ▁the ▁imperial ▁court ▁where ▁he ▁collabor ated ▁with ▁Li ▁J ing x uan ▁and ▁Ma ▁Z ai . ▁ ▁In ▁ 6 7 7 , ▁Western ▁Turk ic ▁Khan ▁Ash ina ▁D uz hi ▁inv aded ▁An xi ▁with ▁his ▁strong ▁forces . ▁At ▁this ▁point ▁of ▁time , ▁Pe i ▁asked ▁for ▁the ▁mission ▁of ▁esc ort ing ▁the ▁Pers ian ▁throne ▁successor ▁N ars ie h ▁to ▁his ▁hom eland . ▁His ▁strategy ▁was ▁to ▁tack le ▁the ▁affairs ▁of ▁Pers ia ▁and ▁Tur ks ▁at ▁the ▁same ▁time . ▁Tang ▁Emperor ▁Ga oz ong ▁not ▁only ▁granted ▁his ▁wish ▁but ▁also ▁gave ▁him ▁the ▁mission ▁of ▁pac ifying ▁the ▁tur bul ences ▁in ▁Central ▁Asia . ▁ ▁During ▁his ▁expedition ▁to ▁the ▁West , ▁he ▁successfully ▁defeated ▁the ▁Turk ic ▁forces ▁led ▁by ▁Ash ina . ▁However , ▁Pe i ▁lost ▁his ▁interests ▁in ▁re install ing ▁the ▁Pers ian ▁King ▁and ▁left ▁N ars ie h ▁in ▁the ▁An xi ▁Prote ctor ate ▁alone ▁( Al though ▁N ars ie h ▁was ▁still ▁able ▁to ▁maintain ▁his ▁many ▁servants ▁and ▁a ▁high ▁quality ▁of ▁life ). ▁Minor ▁Turk ic ▁ch ie ft ains ▁in ▁the ▁region ▁then ▁p led ged ▁their ▁loyal ty ▁to ▁the ▁Chinese ▁dynast y ▁due ▁to ▁the ▁defeat ▁of ▁Ash ina . ▁The ▁overall ▁result ▁of ▁Pe i '