I recall that there is an illustrated Polish Bible (the Wa-something manuscript; I'm afraid I can't recall the exact name) from the thirteenth century (I think?) where the Old Testament figures look exactly like medieval knights. I'm told that a fair amount of what we know about medieval knights--their kit and whatnot--comes from that. I would presume that the artists had no choice but to go with what they knew, and that in fact they had no idea that they didn't know what they didn't know.
Renaissance painters doing biblical scenes would at least put bearded white guys in Oriental robes, so I guess by then they sort of realized that the ancient Hebrews didn't quite look like typical 15th century Florentines?
Did it take the advent of modern archaeology for Europeans to realize that Aristotle and the Apostle Paul weren't rocking the doublet and neck ruff?
hi! Hopefully someone will drop by to address your title question, but as for the issues you raise in the text, you may be interested in some previous discussions on anachronism in medieval art
When medieval and early modern artists portrayed ancient events in contemporary style, did they not know or just not care that it was anachronistic? Why did they do it? - featuring /u/TheJucheisLoose
Why are classical scenes depicted anachronistically in Middle Age and Renaissance art? - featuring /u/GeeJo
When did artists begin to move away from anachronistic depictions of the past, and why? - /u/callmesnake13 looks at The Battle of Alexander at Issus
Were later European painters aware that arms and armor looked substantially different in the classical era as compared to their own time? - /u/WARitter discusses depictions of armour
Were writers and painters in the middle-ages/renaissance aware that they were being anachronistic? - featuring /u/Freevoulous
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