Великолукская область
On 12 July 1929, governorates and uyezds were abolished, and Belsky District with the administrative center in the town of Bely was established. It belonged to Rzhev Okrug of Western Oblast. On August 1, 1930 the okrugs were abolished, and the districts were subordinated directly to the oblast. On 27 September 1937 Western Oblast was abolished and split between Smolensk and Oryol Oblasts. Belsky District was transferred to Smolensk Oblast. During World War II, in 1941—1943, the district was occupied by German troops. On August 22, 1944, the district was transferred to newly established Velikiye Luki Oblast. On October 2, 1957, Velikiye Luki Oblast was abolished, and Belsky District was transferred to Kalinin Oblast. On February 13, 1963 the district was abolished and merged into Nelidovsky District; on November 3, 1965 it was re-established. In 1990, Kalinin Oblast was renamed Tver Oblast.