Ancient and medieval knowledge of the spherical Earth

I expect most of my readers know that Columbus didn't "prove the Earth was round", but an interesting question is how widespread knowledge of the globular Earth was, e.g. among the uneducated. Hard to answer for sure. But this reddit thread gives some interesting quotes about elite knowledge, including citing the Venerable Bede quoting Augustine, and someone writing in 1170s about longitude and time differences (from the observed local time of eclipses.) And:

"the key piece of evidence with regard to unlearned people is a book of sermons published in vernacular German and translated into multiple languages which mentions a spherical Earth multiple times as a metaphor; that is, something ordinary people listening to a sermon would understand and relate to."

Bad news for any Ars Magica campaigns that assume people believing in a flat Earth...

This post discusses the Treaty of Tordesillas; no, a line dividing up the Americas didn't mean they thought the world was flat.

Finally, this blames the 19th century for creating the myth that medieval people thought the world was flat. Not the only historical bullshit that came out of the 19th century...