The withdrawal of Rommel from the East had a deleterious impact on Axis morale and as the Soviet counter-offensive began in the Autumn of 1943, the Germans were forced to gradually withdraw. By winter they had retreated to the Hagen line in front of
Bryansk. In the south, Kharkov which had been won in the summer was lost by winter. This set up 1944 as the critical year where the German Eastern Front would collapse and the Ukraine, Belarus, Novgorod, Latvia, Lithuania, Estonia would be taken by the Soviets by winter.
While the Allies could have advanced on the Ljubljana Gap and attempted to take Vienna, they did not want to relieve German pressure on the east against the Soviets. So the decision was taken to halt the offensive. The decision was made that the Italians could be trusted not to side with the Axis again as soon as the Allied troops left. However several hundred thousand troops would remain behind to guard the Ljubljana Gap. This decision infuriated the Soviets. The Germans would launch several limited offensives in 1944 attacking northeast Italy but fail to make any progress.
This was due to threat from the West persuading Hitler not to devote too much resources on that front. Throughout late 1943 coinciding with the liberation of Italy, the Allies also built up for an invasion of France. With three super liners ferrying men, the various cargo ships could concentrate mostly on ferrying vehicles, ammunition, planes, and other equipment where a sinking would result in few loss of lives. To mislead the Axis, the Allies launched Operation Bodyguard and led the Germans to think they would attack Normandy with Calais and southern France being the diversion to draw away German panzer divisions. In April 1944, a diversion fleet was massed in the area... while the Allies attacked Southern France
It was Operation Vendetta. The Germans had already dissolved the Vichy French govt and taken over the entire country. But they hadn't any time to build many fortifications in the area and the German army was stretched thin: Fighting the Soviets in the east, building and defending the Atlantic Wall, guarding the Ljubljana Gap and Vienna, and now southern France. The largest amphibious invasion in history involving 240,000 men in just the first day coming from Italy coincided with a land offensive against the French Riviera. The operation was a complete success helped by the extremely favourable weather. The initial invasion was followed up by further waves of men coming from North Africa as the three super liners were now plying the transatlantic Gibraltar-Algiers route.
However the Germans continued to think for weeks that it was a diversion tactic with the real target being Normandy. After a few weeks, Rommel finally took his tank divisions south to meet the Allies. But he was bogged down by difficult terrain in the Massif Central. The Royal Navy had also attacked Bordeaux, making transportation of men and tanks beyond the Garonne river impossible. With the Allies making advances using mostly infantry in the Massif Central, Rommel risked being cut off and retreated back to the plains of northern France.