Nova Anglia. Perhaps better to say "might have created settlements". There is a tantalising number of crumbs from place names to travellers reports but little written record. The alleged location would make them the first victims of the Mongolian invasion of Europe a few hundred years later.
Timothy Snyder has a great set of lectures about the making of modern Ukraine and he goes into great detail about the impact the Vikings had in the creation of Rus and their interactions with the Byzantines
https://en.wikipedia.org/wiki/New_England_(medieval)