However significant the long-term effects of external migration on Finnish society may have been, migration within the country had a greater impact--especially the migration which took place between the end of World War II and the mid-1970s, when half the population moved from one part of the country to another. Before World War II, internal migration had first been a centuries-long process of forming settlements ever farther to the north. Later, however, beginning in the second half of the nineteenth century with the coming of Finland's tardy industrialization, there was a slow movement from rural regions toward areas in the south where employment could be found.

Postwar internal migration began with the resettlement within Finland of virtually all the inhabitants of the parts of Karelia ceded to the Soviet Union (see The Continuation War , ch. 1). Somewhat more than 400,000 persons, more than 10 percent of the nation's population, found new homes elsewhere in Finland, often in the less settled regions of the east and the north. In these regions, new land, which they cleared for farming, was provided for the refugees in more populated areas, property was requisitioned. The sudden influx of these settlers was successfully dealt with in just a few years. One of the effects of rural resettlement was an increase in the number of farms during the postwar years, a unique occurrence for industrialized nations of this period (see Agriculture , ch. 3).

It was, however, the postwar economic transformation that caused an even larger movement of people within Finland, a movement known to Finns as the Great Migration (see Economic Development , ch. 3). It was a massive population shift from rural areas, especially those of eastern and northeastern Finland, to the urban, industrialized south (see table 8, Appendix A). People left rural regions because the mechanization of agriculture and the forestry industry had eliminated jobs. The displaced work force went to areas where employment in the expanding industrial and service sectors was available. This movement began in the 1950s, but it was most intense during the 1960s and the first half of the 1970s, assuming proportions that in relative terms were unprecedented for a country outside the Third World. The Great Migration left behind rural areas of abandoned farms with reduced and aging populations, and it allowed the creation of a densely populated postindustrial society in the country's south.

The extent of the demographic shift to the south can be shown by the following figures. Between 1951 and 1975, the population registered an increase of 655,000. During this period, the small province of Uusimaa increased its population by 412,000, growing from 670,000 to 1,092,00 three-quarters of this growth was caused by settlers from other provinces. The population increase experienced by four other south814 thern provinces, the Aland Islands, Turku ja Pori, Hame, and Kymi, taken together with that of Uusimaa amounted to 97 percent of the country's total population increase for these years. The population increase of the central and the northern provinces accounted for the remaining 3 percent. Provinces that experienced an actual population loss during these years were in the east and the northeast--Pohjois-Karjala, Mikkeli, and Kuopio.

One way of visualizing the shift to the south would be to draw a line, bowing slightly to the north, between the port cities of Kotka on the Gulf of Finland and Kaskinen on the Gulf of Bothnia. In 1975 the territory to the south of this line would have contained half of Finland's population. Ten years earlier, such a line, drawn farther to the north to mark off perhaps 20 percent more area, would have encompassed half the population. One hundred years earlier, half the population would have been distributed throughout more than twice as much territory. Another indication of the extent to which Finns were located in the south was that by 1980, approximately 90 percent of them lived in the southernmost 41 percent of Finland.

Data as of December 1988