There is more than ample evidence that European and Asian people were here long long before Christoforo or the Vikings. Here in AZ for example there is a grave of an Englishman that has been dated two hundred years earlier than the Vikings. How they got here and what they were looking for is not known. Maybe came for free medical and food stamps.
He was trying to get home but wouldn’t ask anyone for directions.
I think there were probably lots of visitors to this hemisphere.
In Peru there is a tribe that appears to have Asian ancestry (post land bridge). Their traditional pottery style is nearly identical to a Japanese tribe and they suffer a disease found no where else than the Ainu of northern Japan.
Paging Scott Wolter....