Italy was an important member of the Axis powers in World War II, battling on several fronts with initial success. However, after the German-Italian defeat in Africa and in the Soviet Union and the subsequent Allied landings in Sicily, King Victor Emmanuel III placed Mussolini under arrest, and the Fascist Party in areas (south of Rome) controlled by the Allied invaders was shut down. The new government signed an armistice in September 1943. German forces immediately occupied northern Italy with Fascists' help, setting up the Italian Social Republic, a collaborationist puppet state still led by Mussolini and his Fascist loyalists. As a consequence, the country descended into civil war, with the Italian Co-belligerent Army and the resistance movement contending with the Social Republic's forces and its German allies. Shortly after the war and the liberation of the country, civil discontent led to the institutional referendum on whether Italy would remain a monarchy or become a republic. Italians decided to abandon the monarchy and form the Italian Republic, the present-day Italian state.