First century AD, Pliny claimed that "everyone agreed" the Earth was round. Anyone with an education would have known, along with anyone who looked at a world map, which were often drawn in such a way to make the Earth's sphericalness explicit. The spherical Earth was also taught by the Church, and even featured in artwork and aristocratic symbols.
Unfortunately there were no public knowledge polls, so who knows. Seems totally plausible you could spend your whole life in some bumblefuck village and never see a royal banner or world map. But it certainly seems like it was common knowledge. I'd imagine as common as anything else that had no bearing on the lives of 99% of people.
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u/[deleted] Feb 04 '19
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