Flat Earth Myth

Yeah, no. Ancient societies (say thousands of years ago) do seem to have mostly presumed the world was flat, to the extent we have any records. Mostly though they just didn't care, why should they? But the Ancient Greeks figured out that a Flat Earth doesn't work, observations from their large and growing empire conflicted with the idea of a flat world.

The Flat Earth Myth (that Europeans didn't realise the world was round until Columbus) is just that, a myth. Crazy people insisting an ancient religious work trumps empirical observation existed in Europe at that time, as they still do today, but they weren't the majority and their ideas had little influence. Educated Europeans from e.g. 1400 would recognise a modern globe as a plausible map of the world although only those with the best knowledge of geography would fail to be surprised by how small Europe is in context.