Leif Erikson
Leif Erikson or Leif Ericson ( 970 – c. 1020) was a Norse explorer from Iceland. He was the first known European to have set foot on continental North America (excluding Greenland), before Christopher Columbus. According to the Sagas of Icelanders, he established a Norse settlement at Vinland, tentatively identified with the Norse L'Anse aux Meadows on the northern tip of Newfoundland in modern-day Canada. Later archaeological evidence suggests that Vinland may have been the areas around the Gulf of St. Lawrence and that the L'Anse aux Meadows site was a ship repair station.
John Dee
Dee posited a formal claim to North America on the back of a map drawn in 1577–80; he noted "Circa 1494 Mr Robert Thorn his father, and Mr Eliot of Bristow, discovered Newfound Land." In his "Title Royal" of 1580, he invented the claim that Madog ab Owain Gwynedd had discovered America, with the intention of ensuring that England's claim to the New World was stronger than that of Spain. He further asserted that Brutus of Britain and King Arthur as well as Madog had conquered lands in the Americas and therefore their heir Elizabeth I of England had a priority claim there.