Why did the Norse Icelanders colonize Greenland in the late tenth century A.D., and why did they explore the coasts of Labrador and Newfoundland? Was it a desperate search for farmland at the margins of the known world, or was it a market-driven economic strategy applied to sub-arctic territory? To address these questions, the author gives a brief introduction to the Norse expansion and economic strategies in three regions: the Sami territory in Northern Scandinavia, the Finnish and Russian territories east of Scandinavia, and Greenland and Labrador in the western North Atlantic. The purpose of the expansion north and east of Scandinavia was to buy or extort furs from the hunter-gatherer communities. This strategy is unthinkable without a European and even Middle Eastern demand for furs, and must generally be seen as market-driven. The author suggests that the Norse explorations of Labrador and the colonization of Greenland was equally market driven, with walrus tusks as the most successful export commodity. In the twelfth century, the Norse economy transformed from a Viking Period high-status trade with luxury articles to a low-status bulk trade with foodstuffs. Stockfish from the north was exchanged for grain from the south. Norwegian stockfish export started ca. 1100 A.D., while Iceland commenced almost a century later. This shift caused structural changes to both Norwegian and Icelandic economies, and must also have affected the Norse Greenland economy. The author recommends that the regional and national investigations that have dominated the research be supplemented with North European studies of the Viking and Medieval cash and trade economies, spanning from acquisition to consumption.