Page "Erik the Red" Paragraph 18

The Norse had become separated from their kin in Europe for so long that most of their friendships and alliances had fallen away, hurting some of their trading and eventual protection ; political changes in Europe hastened this process.

Perhaps more significantly, a change in climate in the North Atlantic led to an increase in sea-ice, making communication with Europe difficult, and favoring migrations of the Inuit from northern Greenland to the south and to regular contact with the Norse, leading to violence between the groups.

Finally, and most importantly, the Norse failed to adapt fully to their surroundings.

They clung too much to familiar ways of living that proved ultimately unsuitable in Greenland.