We know for a fact the Vikings made it to the Americas before Columbus. Aside from the Vikings, some of the other leading candidates for pre-Columbian trade and/or colonization in the Americas include:
Phoenicians
Israelis
Carthaginians
Basque
Celto-Iberians
Celto-Hibernians
Irish
Knights Templar
Chinese
Portuguese
Wow, Islam is far more extensive than we thought. :P
The Vikings are different, though.
There is well-documentd archaeological evidence of their settlements in northern Newfoundland, and their voyages were described in 1000-year-old manuscripts left in Denmark, which still exist.
No other “discovering people” can make those claims - even Erdogan’s Muslims.
And I will add ‘Space Aliens’... :-)