Provinces came in two forms. While the guberniia was the more standardized and more prolific form, the oblast' played an important role in the administrative geography of the empire as well.
The oblast' was a secondary administrative unit.
A quick glance at the map reveals that one of the hallmarks of the oblast' was location. If gubernii constituted the "core", the oblast' helped define the periphery of state administration.
From west to east, the 5 oblasts are: Belostok, Bessarabia, Kavkaz (Caucasus), Irkustk, Iakutsk.
