In Bulgaria, okrugs, translated as "districts" or "counties", were the first-level subdivisions of Bulgaria that existed between 1946 and 1987. They correspond approximately to today's oblasts.
Okrugs were a type of administrative division of oblasts and several governorates in Imperial Russia. Until 1920s, okrugs were administrative districts in Cossack hosts.
In the 1920s, okrugs were administrative divisions of oblasts and krais and were, in turn, divided into districts. On July 30, 1930 most of the okrugs were abolished. The remaining okrugs were abolished in the Russian SFSR during 1930–1946, although they were retained in Zakarpattia Oblast of the Ukrainian SSR in status equivalent to that of a district.
National okrugs were first created in the Mountain ASSR of the Russian SFSR in 1921 as units of Soviet autonomy and additional national okrugs were created in the Russian SFSR for the peoples of the north. In 1977, all national okrugs were renamed autonomous okrugs.