Operation Barbarossa also known as the German invasion of the Soviet Union was the code name for the invasion of the Soviet Union by Nazi Germany and some of its Axis allies, which started on Sunday, 22 June 1941, during World War II. The operation put into action Nazi Germany's ideological goal of conquering the western Soviet Union so as to repopulate it with Germans. The German Generalplan Ost aimed to use some of the conquered people as slave labour for the Axis war effort while acquiring the oil reserves of the Caucasus as well as the agricultural resources of various Soviet territories. Their ultimate goal included the eventual extermination, enslavement, Germanization and mass deportation to Siberia of the Slavic peoples, and to create more Lebensraum for Germany.
In the two years leading up to the invasion, Germany and the Soviet Union signed political and economic pacts for strategic purposes. Following the Soviet occupation of Bessarabia and Northern Bukovina, the German High Command began planning an invasion of the Soviet Union in July 1940, which Adolf Hitler authorized on 18 December 1940.