Note 790 — Chapter XII · —Continents And Their Peninsulas

These continental sections of peninsulas become therefore strongly marked as areas of ethnic characterization and differentiated historical development. Their threshold location, by reason of which they first catch any outward migration from the core of the continent, and their fertility, which serves as a perennial lure to new comers, whether peaceful or warlike, combine to give them intense historical activity. They catch the come and go between their wide hinterland and the projection of land beyond, the stimulus of new arrivals and fresh blood. But tragedy too is theirs. The Po Valley has been called "the cockpit of Europe." Even the little Eider, which marks the base of Jutland, has been the scene of war between Danes and Germans since the tenth century.790 The Indus Valley has again and again felt the shock of conflict with invading hordes from the central highlands, and witnessed the establishment of a succession of empires. Peace at the gates of the Balkan Peninsula has never been of long duration, and the postern door of Korea has been stormed often enough.