Fitzhugh (Smithsonian Institute): We've seen ... large amounts of Viking material turning up in native sites in the arctic regions of North America. This material dates to ... 300 years after the initial Vinland voyages. We ... have a time period that began with the Vinland contact episode explorations, and ... after the society in Greenland ... settled, walrus-ivory trade with Europe started to be really important. Probably ... , this stimulated the continuous western orientation of the Greenland Norse, not only up into the Greenland walrus-hunting territories but across the Davis Strait ... These are areas where the Vikings were exploring and trading, and where native populations were trading Viking materials .... Of course, the continuing need for wood in treeless Greenland prompted return visits to ... Labrador.