This is a comparison of the 1950-1970 trends in population size of U.S. nonmetropolitan cities and villages among 26 homogeneous subregions. There are wide variations in the proportion of the nonmetropolitan population in incorporated places, and, though this proportion generally increased over the 1950-1970 period, decentralizing tendencies also are evident. There was most often a decline in the differential between the growth rate of incorporated places and of open country over the two decades. The positive association between initial size of place and growth, present in half of the subregions in the 1950s and indicative of population centralization, was found only in the Corn Belt, Great Plains, and Rocky Mountain subregions in the 1960s. There were regionally distinctive differences in all variables considered; most notably, the percent of places growing ranged 50 percentage points over the 26 subregions. The extent of subregional variation revealed by this analysis indicates how differences in physiography, climate, history, and economy continue to be reflected in settlement trends which are obscured when larger regional groupings are used.