The real understanding of a nation and its evolution depends on an appreciation of the particular combination of physical conditions by which its course has been influenced in the different stages of development. Consequently each nation must be interpreted in terms of its own physical forces, and its strength or weakness may be measured by those forces. The chief physical factors which are important in shaping national development may be grouped, roughly in descending order of importance, under the following general heads: (1) Position with respect to physical relations, (2) position climatically, (3) surface area, (4) surface configuration, (5) productivity of the soil and climate, (6) the possession of potential mechanical energy, (7) mineral wealth.
Physical Position: Separation.—If the conditions necessary for agriculture are assumed to exist, position with respect to physical relations may, on general grounds, be accorded first importance in its effect on national evolution. In the early stages of development of all the older nations, the degree of isolation or separation appears to have been the one significant feature common to all the national territories. This striking similarity may be explained on the ground that unless the primitive group was afforded some degree of protection by natural barriers to attack, the problem of successful establishment and maintenance materially hampered continuity of progress.
A survey of the physical relations surrounding the seats of the early nations of the world indicates the value of separation, since, without exception, they all possessed that quality to a marked degree. Thus, Egypt in the Nile valley, highly favored as it was in soil and climate as a basis for agriculture, may be regarded as owing its early development of national qualities and culture no less to the surrounding desert barrier which guaranteed a large measure of immunity from molestation. For, at the same time, other regions, like the lower Mississippi valley, no less fertile, but lacking protective barriers of any sort, have shown no national development by native groups.
Similar conditions of separation and security were afforded in one way or another in the fertile valleys of western Asia, and in the Greek and Italian peninsulas. Considering Europe as a whole, for example, there are nine fairly distinct physical subdivisions, of which four, the Greek, Italian and Spanish peninsulas and the British Isles, have more or less complete separation, by natural boundaries, from the adjoining continental areas. Each one of the four stands as the seat of solid national development at a date earlier than any stable national existence prevailed in the other parts of the continent, as in the exposed sections occupied by the modern states of Germany and
- For any individual nation at some particular stage in its evolution any one of these factors may stand first in importance, as noted later.