Following the Badoglio Proclamation on 8 September 1943, the announcement of the Armistice of Cassibile, Germany launched an invasion of Italy. Two days later, South Tyrol, Trentino and Belluno came under German control as the Operational Zone of the Alpine Foothills ("Operationszone Alpenvorland", OZAV). This region formally existed under the Italian Social Republic, but was "de facto" ruled by Franz Hofer, the "Gauleiter" of Tyrol-Vorarlberg.