the term "islam" is in quotes since I'm not referring to the actual faith, but to a faith which begins like islam did - a monotheistic religion inspired by a specific culture, which initially gains political dominance through military action/expansion and promotes a specific language.
with this in mind, where and when could a 'roman islam' be born? if it is as effective in spreading latin as islam was with Arabic IOTL, what would be the result of many more latinized provinces? what would be the likeliest theological/philosophical basics for this religion centered around roman culture and customs? how would it be received by the pagans (or Christians, depending on the time of formation)