ub ay r . ▁It ▁ended ▁in ▁a ▁rout ▁for ▁the ▁Um ay y ads ▁and ▁the ▁expansion ▁of ▁M uk ht ar ' s ▁rule ▁into ▁the ▁region ▁of ▁Mos ul . ▁ ▁The ▁Muslim ▁civil ▁war ▁left ▁the ▁Um ay y ad ▁real m ▁restricted ▁to ▁Dam asc us ▁and ▁its ▁en vir ons ▁after ▁most ▁of ▁their ▁territ ories ▁came ▁under ▁I bn ▁al - Z ub ay r ' s ▁orbit . ▁However , ▁an ▁Um ay y ad ▁res urg ence ▁began ▁with ▁the ▁acc ession ▁of ▁C ali ph ▁Mar wan ▁I , ▁who ▁dispatch ed ▁an ▁army ▁led ▁by ▁U bay d ▁Al lah ▁ibn ▁Z iy ad ▁to ▁recon quer ▁Ira q . ▁This ▁army ' s ▁advance ▁into ▁Mos ul ▁precip itated ▁the ▁Battle ▁of ▁Kh az ir ▁and ▁its ▁commander , ▁U bay d ▁Al lah , ▁was ▁an ▁enemy ▁of ▁M uk ht ar ' s ▁pro - Al id ▁part is ans . ▁Thus , ▁M uk ht ar ▁quickly ▁moved ▁to ▁halt ▁the ▁Um ay y ad ▁advance , ▁sending ▁his ▁Pers ian ▁ma w ā l ī - domin ated ▁forces ▁led ▁by ▁I bra him ▁ibn ▁al - As ht ar ▁to ▁confront ▁the ▁pre domin antly ▁Sy rian ▁Arab ▁army ▁of ▁the ▁Um ay y ads . ▁During ▁the ▁initial ▁combat , ▁part ▁of ▁I bn ▁al - As ht ar ' s ▁forces ▁were ▁put ▁to ▁flight , ▁but ▁then ▁re group ed ▁under ▁his ▁command