Arianism appealed to many high-level leaders and clergy in both the Western and Eastern empires. Although the western Emperor Gratian () supported orthodoxy, his younger half brother Valentinian II, who became his colleague in the empire in 375, adhered to the Arian creed. Ambrose sought to refute Arian propositions theologically, but Ambrose did not sway the young prince's position. In the East, Emperor Theodosius I () likewise professed the Nicene creed; but there were many adherents of Arianism throughout his dominions, especially among the higher clergy.
ARIANism AppEaleD to mANy High-levEL lEAderS and clergy IN both The westErn and eASterN empIres. aLTHouGh tHe weSterN EmperOr gratIan () sUPported oRThoDoxy, hiS youngEr hALf BRothER vALeNtinian Ii, who bEcame hIs COlLEAgUe iN thE EmpiRe In 375, adhERed to The arIan cREed. amBrosE sought To Refute aRIan propOsitioNS tHeoLogicaLly, bUt ambROSE dId not sWay the yOung PriNce's poSItioN. iN THE eaSt, empeRoR TheoDosius i () lIKewise prOfeSseD thE nicene cReEd; But thERe WEre many adheReNTs of arIanism tHrOughouT hIs dOMiNioNs, esPecialLY aMOnG tHe HigheR cleRgy.