I heard the Irish traveled with the Vikings to Eastern North America or at least to Iceland and Greenland. Everyone else in Europe hated them so they took up with the Vikings.
Pat B,
Everyone in Europe hated Everyone else. I doubt if most had come across the Irish, they were not renowned for their travel. Also far from joining with the Vikings they were invaded by the Vikings, Dublin was a Viking city. If any Irish travelled with the Vikings they were more likely to be slaves than free.
KenH,
The Irish travelled to NA on their very own! Read The Brendan Voyage by Tim Severin
The fact that someone travelled in the manner that legend says someone else did does not prove that the original is any more than a legend or wishful thinking. Look at Tor Heyerdahl and the Kon-tiki. He showed it was possible the raft could travel the distance but genetics has shown the theory that Polynesians came from South America to be wrong.
Craig.