Christianity, at this time, had already incorporated many pagan things ( making pagan gods saints, making pagan "holy sites" Christian ones, and the highest social strata were 100% Catholic, whilst many of non-Norman French/the lowest serfs, still clung to some very old pagan customs.
I think I didn’t fully articulate the relevant points.
If we are to deal adequately with different spiritual beliefs, we must define the particular belief systems we are discussing.
First, we should understand that Christianity necessarily means belief in Jesus Christ as King of kings (all kings) and Lord of lords (all lords) and as Savior, the door to everlasting life. So that if a pagan deity creeps into any given individual’s belief system and pretends to displace Christ, then that belief system has been changed to from something other than Christianity to paganism. (The latter has many forms but as a whole represents no particular theology beyond a denial of Christ.)
And if we are looking at how spiritual beliefs are distributed among various socioeconomic classes, why would we ignore the dark prominence of luciferian doctrine amongst the highest elites?