Allied invasion of Italy the Mediterranean theatre, and it was they who planned and commanded the invasion of Sicily and the Italian mainland. The Allied invasion of Sicily in July 1943, codenamed Operation Husky, was highly successful, although many of the Axis forces managed to avoid capture and escape to the mainland. The Axis viewed this as a success. More importantly, in late July, "a coup" deposed Mussolini as head of the Italian government, which then began approaching the Allies to make peace. It was believed a quick invasion of Italy might hasten an Italian surrender and produce quick military victories over the German
Operation Avalanche the Allied armies a grinding and attritional slog against skillful, determined and well prepared defenses in terrain and weather conditions which favoured defense and hampered the Allied advantages in mechanised equipment and air superiority. It took until mid-January 1944 to fight through the Volturno, Barbara and Bernhardt lines to reach the Gustav Line, the backbone of the Winter Line defenses, setting the scene for the four Battles of Monte Cassino which took place between January and May 1944. Operation Avalanche Operation Avalanche was the codename for the Allied landings near the port of Salerno, executed on 9 September 1943, part