Before revision: Kouvola was annexed to Vyborg Province in 1922-1945 but in 1940 and 1944, most of Vyborg County was ceded to the Soviet Union, and the remaining areas were formed into Kymi Province in 1945.
After revision: Kouvola was annexed to Viipuri Province in 1922–1945 but in 1940 and 1944, most of Viipuri County was ceded to the Soviet Union, and the remaining areas were formed into Kymi Province in 1945.