As part of the Russian Empire, the city was called "Dvinsk" from 1893 to 1920. The newly independent Latvian state renamed it "Daugavpils" in 1920. Latvians, Poles and Soviet troops fought the Battle of Daugavpils in the area from 1919 to 1920. Daugavpils and the whole of Latvia was under the Soviet Union rule between 1940–41 and 1944–1991, while Germany occupied it between 1941 and 1944. The Nazis established the Daugavpils Ghetto where the town's Jews were forced to live. Most were murdered. During the Cold War the Lociki air-base operated northeast of Daugavpils itself. In the late Soviet era, there was a proposal to build a hydroelectric power station on the Daugava river that was successfully opposed by the nascent environmental movement in Latvia.