The first European known to have seen North America (apart from Greenland) was Bjarni Herjolfsson in 986. He was trying to get to Greenland and missed it—he saw parts of the Canadian coast (Baffin Island and Labrador, perhaps Newfoundland) but did not go ashore. He eventually reached Greenland and told people what he had seen—they made fun of him for never going ashore. Leif Eriksson knew about his discoveries when he made his explorations in or about the year A.D. 1000.
St. Brendan 6th Century