Collapse_ How Societies Choose to Fail or Succeed - Jared Diamond [117]
Perhaps the most important consequence of the colonists’ conversion to Christianity involved how they viewed themselves. The outcome reminds me of how Australians, long after the founding of Britain’s Australian colonies in 1788, continued to think of themselves not as an Asian and Pacific people but as overseas British, still prepared to die in 1915 at far-off Gallipoli fighting with the British against Turks irrelevant to Australia’s national interests. In the same way, Viking colonists on the North Atlantic islands thought of themselves as European Christians. They kept in step with mainland changes in church architecture, burial customs, and units of measurement. That shared identity enabled a few thousand Greenlanders to cooperate with each other, withstand hardships, and maintain their existence in a harsh environment for four centuries. As we shall see, it also prevented them from learning from the Inuit, and from modifying their identity in ways that might have permitted them to survive beyond four centuries.
The six Viking colonies on North Atlantic islands constitute six parallel experiments in establishing societies derived from the same ancestral source. As I mentioned at the beginning of this chapter, those six experiments resulted in different outcomes: the Orkney, Shetland, and Faeroe colonies have continued to exist for more than a thousand years without their survival ever being in serious doubt; the Iceland colony also persisted but had to overcome poverty and serious political difficulties; the Greenland Norse died out after about 450 years; and the Vinland colony was abandoned within the first decade. Those differing outcomes are clearly related to environmental differences among the colonies. The four main environmental variables responsible for the different outcomes appear to be: ocean distances or sailing times by ship from Norway and Britain; resistance offered by non-Viking inhabitants, if there were any; suitability for agriculture, depending especially on latitude and local climate; and environmental fragility, especially susceptibility to soil erosion and deforestation.
With only six experimental outcomes but four variables that might explain those outcomes, we cannot hope to proceed in our search for explanations as we did in the Pacific, where we had 81 outcomes (81 islands) compared to only nine explanatory variables. For statistical correlational analysis to have any chance of succeeding, one needs many more separate experimental outcomes than there are variables to be tested. Hence, in the Pacific, with so many islands available, statistical analysis alone sufficed to determine the relative importance of those independent variables. In the North Atlantic, there are not nearly enough separate natural experiments to achieve that aim. A statistician, presented only with that information, would declare the Viking problem to be insoluble. This will be a frequent dilemma for historians trying to apply the comparative method to problems of human history: apparently too many potentially independent variables, and far too few separate outcomes to establish those variables’ importance statistically.
But historians know much more about human societies than just the initial environmental conditions and the final outcomes: they also have huge quantities of information about the sequence of steps connecting initial conditions to outcomes. Specifically, Viking scholars can test the importance of ocean sailing times by counting recorded numbers of ship sailings and reported cargos of the ships; they can test effects of indigenous resistance by historical accounts of fighting between Viking invaders and the locals; they can test suitability for agriculture by records of what plant and livestock species