With the fall of the Fascist regime in Italy in July 1943 following the Allied invasion of Sicily, Mussolini was deposed as dictator and placed under arrest. In September of that year, the Allies launched the invasion of mainland Italy from the south. In the same month, German special forces rescued Mussolini in the Gran Sasso raid and Hitler installed him as leader of the Italian Social Republic, a German puppet state in the Axis-controlled northern half of the country, and based at the town of Salò near Lake Garda. By 1944, the "Salò Republic", as it came to be called, was threatened not only by the Allies advancing from the south but also internally by Italian anti-fascist partisans, in a brutal conflict that was to become known as the Italian civil war.