Pepe it's not clear from your post whether you are asking that both be allowed or both disallowed
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well how I read it anyway. But then it's you, so guessing the latter
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lol in theory our character names should be anything we want because the era we are playing in is supposedly pre 1500's, before any of these dudes existed BUT this is the internet where people get offended about shit.
The Mongol horsemen of Temüjin under Genghis Khan were known to kill whole nations, total genocide. Also some dude I think called Tamerlane caused 17m deaths with his rule, about 5% of the worlds population at that time. We'd be offended by these more relevant names, and ask for name changes too? Or are they too far in history to care - yet people still suffered terribly.
It opens up a can of worms I guess.
Another thing, the name H it ler, was just a mangle of the original surname Hiedler (also Huetler, Huettler), which are still somewhat in use today. That's just interesting fact of the morning
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not relevant to the discussion.