Thorfinn Karlsefni, an Icelandic explorer of the 11th century, believed to have been the first to attempt to found a permanent settlement in North America. Early in the 11th century, he sailed for Greenland. There he married Gudrid, widow of Thorstein Ericson (brother of Leif Ericson, who had discovered a North American land called Vinland). Shortly after his marriage, he led an expedition of about 160 persons bound for Vinland.

Thorfinn and his party first came upon what they thought to be Helluland, a region named by Leif Ericson. After exploring to the southeast, they reached what was supposedly Vinland. They settled at a bay that they called Hóp. However, dissension and hostile natives forced Thorfinn to return his party to Greenland within a few years. (Many scholars believe that eastern Canada may have been the site of Thorfinn's explorations.)