No original stewards. Native Americans migrated from asia.
Agreed 100%. All evidence points to our species migrating out of tropical Africa. We only know of three Homo Sapiens civilizations that developed independently: The West (Western & Central Eurasia, including our own), the Far East (China & Southeast Asia), and the Mesoamerican empires (roughly bound by the US-Mexico border to the north and Chile to the south).
My primary source was the book “Guns, Germs and Steel”.