Who are the "Skrælings" from The Vinland Sagas: The Norse Discovery of America?

A 'Skræling' is the name that Norse settlers of Greenland gave to the Thule people (probably Inuit) in Greenland, but they used the same name for the Native Americans they encountered in Newfoundland, who are probably the ancestors of the Beothuk. 'Skræling' means barbarian or foreigner. In the sagas, the Skrælings are so numerous and barbaric that Karlsefni decides to take his settlement and leave Vinland.