The RAF's planned campaign objectives for the night bombing campaign against Italy was laid out in this excerpt from the "Defeat of Italy by Air Attack Alone" report, issued by the Joint Intelligence Sub-Committee. 16 April 1943.
"The industrial life of Italy as a whole depends upon the North... If this weight of attack could be concentrated on the main centers of Italian industry such as Milan, Turin and Genoa, it would effectively paralyze activity at those centers, create widespread civil chaos and conditions such that it would be impossible to continue to plan the supply and maintenance of Italy's armed forces."
On 10 June 1940, Air-Vice Marshall Norman Bottomly issued "Operation Instruction No. 36". This document highlighted that Bomber Command's objectives in attacking Italy were:
"... to cripple the Italian aircraft industry, to destroy stocks of oil, and to cause widespread disturbance and demoralization amongst the Italian population, especially in the Northern Industrial Area."
The first bombing raid into Italy by RAF Bomber Command occurred on 11/12 June 1940. The results were rather poor as only a few of the 36 Whitley bombers dispatched made it to their targets. Following this abysmal start, RAF Bomber Command conducted a few additional night raids into Northern Italy into mid July 1940 when Bomber Command curtailed Italian missions to assist in bombing German naval targets gathering for the invasion of Britain along the French coastline.
Bomber Command resumed Italian night bombing missions beginning in mid-August 1940 that ran until August 1943. As the fortunes of Italy waned, Bomber Command gradually increased the strength of the raids with Milan, Genoa, and Turin bearing the brunt of the attacks. In August 1943 as word of a possible Italian surrender got around, the bombings ceased and soon after the Italians capitulated.
From the start of the night raids in 1940 until the Spring of 1942, the Armstrong Whitworth Whitley was the aircraft of choice. The Whitley then filled the gap until enough of the four- engine bombers (Stirling, Halifax, and Lancaster) were available.
The Italians were not prepared for these night raids and could do little to stop them. They had no purpose built night fighters. Italy's performance in the Spanish Civil War led the Government to believe that Italian Aircraft were unbeatable on the offense and air defense measures were not necessary.
Italy's General Francesco, Chief of the Air Staff from 1939 to 1941 believed that Italy was protected by the Alps and with Germany's stunning conquests in Europe a strong night fighter air defense was not necessary anyway as Germany would soon sweep aside England as he had done with the other European countries.
Italy started the war with no established night fighter early warning detection systems in place and no dedicated night fighters. In June 1940, Italy's Regia Aeronautica boasted about 3000 aircraft. Most were antiquated designs like the Fiat CR-42, a biplane with open cockpit and light armament that comprised 1782 of the 3000 aircraft in Italy's air force. The Regia Aeronautica was mainly a day fighter force. There was little training in night fighter tactics and the Italian Air Force tended to use small sections of enthusiastic pilots attached to day fighter units in the night fighter role.
The Italian concept of night fighter operations was soon shown to be incorrect. Frantic pleas for assistance to Germany resulted in less than faithful help. A few Messerschmitt Me-110 C model day fighters were sent to the Italians. They had no electronic detection equipment installed to function as night fighters. Germany did eventually send their 2nd Nachtjadgeschwader to Italy in 1943, but it arrived too late to make a difference.
The Italian Air Defense System lacked a reliable radio system and had no ground-controlled electronic radar line like the German "Kammhuber Line" in Europe. The mountainous terrain of northern Italy effectively blocked radar and radio communications needed to direct night fighters to their airborne targets from ground control stations. Italy had to rely upon ground observers, sound detection equipment and search lights to detect bombers coming in over the Alps.
Between September 1942 and the summer of 1943, with German help, a rudimentary electronic night fighter detection system was in place. The Germans formed a "Kammhuber Line' across northern Italy comprising 33 "Himmelbett" boxes, but it wasn’t effective because of poor radar and radio communications.
Germany did train a few Italian night fighter pilots at their night fighter training school at Schleissheim beginning in 1942. Italian pilots who were trained in Germany and Italy did receive a few Do-217 night fighters. The Italians ended up converting the CR-42, Re-2001, and D520 into night fighters. Italian night fighter pilots were not aggressive and when they did have an opportunity to intercept, usually one pass was all that was done.
The defense of Italian cities against air attack was primarily left to Anti-Aircraft Artillery batteries and Searchlights. Like Italy's Air Force, Italy's Anti-Aircraft Artillery was World War One vintage. Due to a chronic lack of funding during the 1930s, new and more modern weapons and equipment were not purchased and training was minimal. In December 1942 after repeated requests from Mussolini, Hitler dispatched 100 batteries of 88mm Anti-Aircraft Artillery and 30 Search Light batteries with German crews to bolster Italy's sagging AAA defenses.
Most RAF Bomber Command losses from these missions were due to malfunctions, fuel starvation and attacks by German and Vichy French day and night fighters as the bombers travelled through France. Bomber Command made 55 attacks on Italy during the period of June, 1940 to August 1943 with 4,075 aircraft attacking their designated targets. Of those aircraft, 94 were lost – an overall 2.3% loss rate.