What do invented saints tell us about Christianity?

[Belacqua]

Granted, it's harder to know the beliefs of the illiterates, because they didn't write things down. 

On the other hand, since the educated people all knew that earth is a sphere, we don't know how far this was passed on to less-educated people. 

Do you have any historical source making this specific claim -- that the rank and file believed in a flat earth? I don't want to assume it's true without any evidence.

Again, it's in Wikipedia -- some of the pre-Nicene Church fathers believed in a flat Earth.

This is what I see on Wikipedia:

During the early period of the Christian Church, the spherical view continued to be widely held, with some notable exceptions.