Operation Avalanche and the Italian mainland. The Allied invasion of Sicily in July 1943, codenamed Operation Husky, was highly successful, although many of the Axis forces there were allowed to avoid capture and escape to the mainland. More importantly a "coup" deposed Benito 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 troops that would now be trapped fighting in a hostile country. However, Italian (and more so German) resistance proved relatively strong, and
Allied invasion of Sicily opportunistic and irrelevant, but were persuaded to agree to a Sicilian invasion on the grounds of the great savings to Allied shipping that would result from the opening of the Mediterranean by the removal of Axis air and naval forces from the island. The Combined Chiefs of Staff appointed General Eisenhower as C-in-C of the Allied Expeditionary Force, General Alexander as Deputy C-in-C with responsibility for detailed planning and execution of the operation, Admiral Cunningham as Naval Commander, and Air Chief Marshal Tedder as Air Commander. The outline plan given to Eisenhower by the Chiefs of Staff involved dispersed landings