I just learned the other day that the Visigoths and most Germans who originally converted to Christianity converted as Arians which means they didn't believe in the holy trinity. They believed Jesus came from God but wasn't God.
Truthfully, this is what I've always believed about Christianity also but I never knew the term was Arian or that it was a fairly popular belief until the Catholic Church forced everyone to convert to the Holy Trinity belief system.
There are whites that follow Islam though. Just not typically Europeans (only european states that do are Bosnia and Albania, but albania is mostly atheist and bosnians can't follow the Quran worth a fuck). The chechens are probably the best example of whites following Islam. If you want to get technical, levantines following Islam are white, mostly