Sevsk is a town and the administrative center of Sevsky District in Bryansk Oblast, Russia, located on the Sev River, 142 kilometers from Bryans…Sevsk is a town and the administrative center of Sevsky District in Bryansk Oblast, Russia, located on the Sev River, 142 kilometers from Bryansk, the administrative center of the oblast. Population: 6,732 ; 7,282 ; 7,660 ; 7,820.