In the history of the Greeks the centre of interest lies, not in their peninsula, but in the coasts and islands of the Aegean sea, which collectively formed the very heart of Hellas. It was not till they had passed the zenith of their development that the interior and north of the mainland came into prominence. For their beginnings it is instructive to take note of their situation in the great cultural area which borders the eastern half of the Mediterranean Sea. In this area mankind first emerged from barbarism. It is a region which at the dawn of history was especially subject to immigration. We may infer, then, that from concentration, added to natural growth, and the population became too dense to find support in hunting, fishing and gathering wild fruits and nuts. The productive valleys of the Nile and the Euphrates, and to a less degree the small alluvial plains at the mouths of the rivers on both Aegean coasts, invited to agriculture. From tilling the soil, however rudely, to the higher stages of civilization the way was comparatively easy.            This development was favored by the mild, sub-tropical climate. Less enervating than the equatorial heat, it yet rendered life far easier than is possible in the temperate zones. On the Mediterranean shores men need less food, clothing, and shelter. They live more in the open air in social contact with one another. Thus their struggle for existence is not all-absorbing; they have more leisure to devote to thought and to the creation of the adornments of life and more opportunity for discussion, for the interchange and clarification of ideas...