Around 982 c.e., a Viking called Erik the Red discovered two clement fjords that ran into the ice mass of Greenland. On the lower slopes of the fjords there were green pastures; above, dark forests. It looked a little like Norway. Within a few generations there were 5,000 Norse colonists living in Greenland. They built a cathedral, traded walrus tusks for European luxuries, and farmed cattle as they had at home.

But Greenland is not Norway. It is desperately inhospitable. Consider, for example, how the colonists raised cattle: they built low barns in which they lived with their cows for nine months of the year. Each cow was kept in its own tiny stall. The Viking cows were dwarves, just over four feet tall. During winter, they were fed hay the colonists harvested during the short summer. After bad harvests, the hay would run out. Then the colonists would force the cows to eat seaweed, which made the cows sick. When the ice melted in May, the cows were too weak to walk; they were carried outside to eat the new grass.