Because depression has been greatest near the Aegean, Medi terranean influences penetrate towards the interior here, affect ing both the climate and the crops. Thus irrigation is often nec essary for summer crops, and has been practised for a prolonged period. The prevailing cereals of the west give place to a much greater variety of products, including the vine, the mulberry for silk production, and fruit-trees, especially the fig, as well as crops like cotton, tobacco, poppy, red peppers, maize, rice, with a great number of vegetables.
In Turkish, as in Byzantine times, the high basins of the west, and much more the lower and more productive ones of the Vardar-Struma region, made Macedonia a highly-valued posses sion. Since the great highway which follows the Vardar valley is continued along the seaboard through Thrace to Constantinople, it was a relatively easy matter to hold it, so long as military power was unimpaired. Further, the fact that some of the main routes of the peninsula pass through Macedonia made it essential that any empire based on Constantihople should hold the region, alto gether apart from its productivity. It is sufficient to note that Albania, Bosnia, Hercegovina and Old Serbia could only be reached from the Turkish capital through Macedonia.
In Turkish times the Christian cultivators of the basins felt the full weight of Turkish misrule, all the more because escape was impossible, the over-lords being widely spread along the lines of the highways. The question of the actual composition of the population was a difficult one, even before it was complicated by propaganda on the part of the nationalities concerned, and forced or voluntary movements. There was, and still is in places, a considerable Muslim element, not necessarily ethnically Turkish, but sharing in the privileges of the ruling race. Since the moun tainous country in the west is no barrier to the Albanians, who ap pear to prefer hilly areas, and since further the Turkish adminis tration showed little desire to interfere either with Albanian raid ing or Albanian settlement at the expense of the Macedonian peasants, there was a considerable Albanian element.
The nomadic Vlachs, moving with their flocks from the high pastures in the warmer season to the low-lying ones near the Aegean in the colder one, found in Macedonia a region peculiarly fitted to their mode of life. Neither here nor elsewhere in the peninsula, however, do they enter to any extent into the nation ality problem, being easily assimilated, and having no contiguous homeland to serve as a centre of propaganda. Even in Turkish times there appears to have been a considerable infiltration of Greek peasants from the south, especially in those areas which approximate in climate, natural vegetation and cultivated crops to the Greek lands proper. Here also, as elsewhere, the Greeks tend to be town-dwellers, owing to their instinct for trade. The mass of the peasant cultivators are generally believed to have always been Bulgarian or modified Bulgarian. A true Serb ele ment was probably never large, but the memories of mediaeval Serbia and of the heroic if unavailing stand made by the Serbs against the first advance of the Turks, gave Serbia a sentimental claim, and the Serbs also assert that the greater part of the popu• lation is modified Slav rather than truly Bulgarian.