Fascist Italy was a leading member of the Axis powers in World War II. By 1943, the German-Italian defeat on multiple fronts and the subsequent Allied landings in Sicily led to the fall of the Fascist regime, and Mussolini was placed under arrest by order of the King Victor Emmanuel III. The new government signed an armistice with the Allies on September 1943. German forces occupied northern and central Italy, 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.