oblast (ōˈbläst, ŏˈ–, Rus. ôˈbləstyə) [key] [Rus., = region], administrative and territorial division in Russia, Ukraine, Belarus, and the former USSR. In the USSR, oblasts in which the majority of the population was of a nationality different from that of the constituent republic in which they were included generally enjoyed autonomous status. There is only one surviving autonomous oblast in Russia; the others became republics. The boundaries of oblasts are usually based on economic and administrative considerations; as a result, oblasts vary considerably in size and population.
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