Western Europe, like India, is a peninsula of Asia.
definition would include all the territory that came to form part of
western Christendom in the Middle Ages. This domain stretches from
Spain and Italy in the south to Scandinavia in the north, from Ireland
in the west to Lithuania in the east.
Northwestern Europe encompasses Britain, the Low Countries,
northern Germany. These are as among the most densely populated parts
of the world. The region lies at the same latitude as Labrador and the
Kamchatka, two forlorn and frigid peninsulas that typify a vast swath
of territory located too close to the Arctic for human comfort. Yet
Europe, and especially northwestern Europe, stands out in sharp
contrast to North America and Asia. Unlike Labrador and the Kamchatka,
this region enjoys a temperate climate: a winter that is not so cold as
to preclude the survival of a dense population, a summer that allows an
adequate growing season, and plenty of rain. This climate is the gift
of the Atlantic or, more precisely, of the way seawater circulates in
it, bringing warm tropical water to the shores of Europe. Like so much
else in the world, this system is likely to be contingent. There may
have been no such pattern of circulation in the last ice age, and there
may be none when the climate takes its next lurch. Perhaps nowhere is
the idea of a fleeting Holocene window of opportunity more in place
than in northwestern Europe.