The "Luftwaffe" proved instrumental in the German victories across Poland and Western Europe in 1939 and 1940. During the Battle of Britain, however, despite inflicting severe damage to the RAF's infrastructure and, during the subsequent Blitz, devastating many British cities, the German air force failed to batter the beleaguered British into submission. From 1942, Allied bombing campaigns gradually destroyed the "Luftwaffe"s fighter arm. From late 1942, the "Luftwaffe" used its surplus ground support and other personnel to raise "Luftwaffe" Field Divisions. In addition to its service in the West, the "Luftwaffe" operated over the Soviet Union, North Africa and Southern Europe. Despite its belated use of advanced turbojet and rocket-propelled aircraft for the destruction of Allied bombers, the "Luftwaffe" was overwhelmed by the Allies' superior numbers and improved tactics, and a lack of trained pilots and aviation fuel. In January 1945, during the closing stages of the Battle of the Bulge, the "Luftwaffe" made a last-ditch effort to win air superiority, and met with failure. With rapidly dwindling supplies of petroleum, oil, and lubricants after this campaign, and as part of the entire combined "Wehrmacht" military forces as a whole, the "Luftwaffe" ceased to be an effective fighting force.