The occupation of Belarus by Nazi Germany started with the German invasion of the Soviet Union on June 22, 1941 (Operation Barbarossa) and ended in August 1944 with the Soviet Operation Bagration. The western parts of the Belorussian Soviet Socialist Republic (as of 1940) became part of the Reichskommissariat Ostland in 1941, but in 1943 the German authorities allowed local collaborators to set up a client state, the Belarusian Central Rada, that lasted until the Soviets liberated the region.