That is only according to what we know so far, but actually there are scattered historical evidences of precolumbian contacts , they found roman , cartaginean , chinese and other ancient countries stuff in american territories.
Not enough for shooting out precolumbian contacts , but still existant to make the claim that there were no contacts negligible.
SO even if canon archeology and history tells us there were no contacts, it doesn't actually means its true .
Teuchitlan
I would instead add the americas , because even in ancient times there were pretty interesting nations there, like
Olmec or
Teotihuacán ,
Teuchitla,
Huastec ,
Calima,
Chavín, etc..
And random new and africa and asian world eventually

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I would really like to play as Qin Shi Huang and play the warring states campaign in 210 BC

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