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Newport, RI

The contents of this paper reflect my own personal views and are not necessarily endorsed by the Naval War College, the Royal Australian Navy or the US Department of the Navy.

The Italian Fleet and submarine arm turned out to be not nearly as effective as their strength had led both friend and foe to expect.

Kriegsmarine Admiral Karl Doenitz,Commander in Chief of U-Boats


When Fascist Italy commenced hostilities in June 1940 it reinforced the German anti-shipping campaign with one of the largest Submarine Forces in the world. Kriegsmarine commanders expected that the Regia Marina’s 113 submarines would significantly bridge the gap between the 55 U-boats the Germans had available and the 300 required to effectively blockade the British Isles.1However, despite some spectacular but isolated successes, the Italians failed to deliver substantial operational results and by the September 1943 armistice 85 of their submarines had been destroyed.2Yet it would be incorrect to dismiss the Italians as ineptly led or poorly manned like other elements of the Il Duce’s military machine. Instead, analysis shows that antiquated doctrine, poor integration with their German allies, and technical deficiencies combined to reduce the Italian submarine force’s effectiveness.These factors continue to be critical aspects in combined maritime operations today.

The Regia Marina Submarine Force

Experiencing a substantially different style of operations during WWI in comparison to the Germans, the Italian Navy developed different submarine concepts of operations and design philosophies between the wars. By the eve of WWII, Italian Submarine Force had become the orphan of an ill-defined naval strategy and had been assigned diverse roles including: coastal defense, enemy fleet interdiction, fleet scouting, mine laying, destruction of enemy shipping, and the transportation of essential war material. This led the Italians to develop a diverse Submarine Force to fulfill these roles throughout the 1920s and 30s. As a result, the Italians commenced hostilities in June 1940 with 113 boats of more than two dozen designs.

Contemporary analysis by Germans and Allies alike concluded that the Italian Submarine Force could have been a potentially decisive factor in the early days of the Atlantic War, but this did not eventuate. This failure to deliver was not due to cowardice or ineptitude. Like the Kriegsmarine, the Regia Marina had its celebrated heroes and some were recognized with significant German decorations in addition to Italian awards. Admiral Doenitz himself noted that ‘[the Italians] are perfectly capable of delivering an assault with great gallantry and devotion…often display greater dash and daring than the Germans, who are less prone to be carried away by the thrill of battle.’ The challenging Gibraltar Straits choke point was notoriously difficult to negotiate yet the Italians managed to do so on forty occasions in both directions losing only one submarine in the process, so a lack of mariner skills is not to blame. Arguably, Italian submarines were the most widely deployed boats of any nation in WWII. In addition to the Mediterranean and the North and South Atlantic Oceans, Italian submarines operated in the Red Sea and Northern Indian Ocean as part of the naval defenses of the Italian colonies, and in later periods midget submarines were deployed into the Black Sea while fleet submarines conducted long-range supply trips of critical war materiel to the Japanese in the Far East. These far-flung operations are demonstrative of a capable support network, so if logistic failures did not reduce operational effectiveness what did and what are the applicable measures of effectiveness?

In the Axis anti-shipping campaign operational success was measured in merchant tonnage sunk. However, the Mediterranean and Atlantic operational environments were significantly different in this regard, particularly in regard to the level of enemy merchant activity (i.e. target availability). When employed to their strengths (solitary operations in areas of independent merchant steaming with low enemy aircraft activity), the Italians performed quite credibly. Overall their output was sound but at a rate of effort below German expectations and performance.11The most successful Italian submarines in terms of tonnage were the 32 submarines in the Atlantic which sank 109 vessels between 1940-43; an aggregate of almost half a millions gross tons, but with half these boats lost on operations the cost was high. In considering the Italian performance;doctrine and training, integration, and technical capabilities are the critical areas in which the Italians were found wanting.

Doctrine and Training

When Italy entered the war one of the greatest challenges facing its submarine arm was a lack of suitably qualified and experienced crews. Perhaps more limiting was a failure to understand the modernization of submarine warfare, which left them with antiquated doctrine based on their WWI Adriatic experience. This was reinforced by incorrect lessons learned from the Italian submarine contributions to the Spanish Civil War in 1937 where they had shown some ability to intercept independent merchant vessels in otherwise benign conditions. As a result, Italian submarine tactics were significantly less advanced in comparison to German developments prior to the war. While the Germans favored surfaced night attacks using diesel engines to achieve full speed for maneuver and intercept, the Italians preferred to lie in wait submerged. German Wolf Pack tactics called for a group of submarines to attack en mass to maximize confusion and overwhelm the escorts, while the Italians employed their submarines in independent patrol areas. Like the Germans initially, the Italians favored surfaced gun attacks against lone merchantmen to conserve precious torpedoes but persisted with this tactic long after it became imprudent. These aspects not only made the Italians less effective in the relative dearth of merchant traffic of the Mediterranean, it hampered their integration into broader German operations in the Atlantic.18Having completed a detailed inspection on the Italian boats in the combined base at Bordeaux in 1940, Krieg smarine officers reported to Admiral Doenitz that their new allies had ‘a lack of tactical ideas and tactical training of the submarines’ officers, though they are very dynamic and good willing.’19But instead of addressing these shortfalls, the Italian submarines were deployed to areas where Allied convoy procedures were absent or less robust, and where they were more likely to avoid enemy aircraft.20A prime opportunity to develop a militarily effective partnership was squandered, much to the advantage of the Allies.

Contemporary accounts also suggest that the Italian submariners did not enter the war with a mindset ready for unrestricted hostilities. Italian commanders had a culture of prioritizing the more glamorous warship targets in preference to the merchant vessels that contributed to the enemy economy. Furthermore, some Italian commanders showed great humanity and compassion, including remaining surfaced for extended periods to tow lifeboats filled with merchant sailors to safety rather than abandon them on the high seas. The Germans specifically banned such practices but Italian submariners remained quietly impressed with such bravado and chivalry. This was not the mindset of a force focused or trained for unrestricted submarine warfare.

The Regia Marina had schools and facilities to train submariner officers and crews but the diverse roles and methods of employment made their integration with the German U-boats problematic. This went deeper though, with differing methods of communication, convoy reporting, and even weather observations making the Italian contributions unappreciated by the Germans to the point where they appear to have been written off somewhat uncharitably by Doenitz himself by 1941 despite his desperation for more platforms at sea. While there were efforts to train some Italians in the German training squadrons in the Baltic, these efforts appear haphazard and inconsistent. Further complicating the Italian efforts was their own lack of effective anti-submarine capabilities. Not only did this have operational impacts for their surface fleet defenses, it hindered their own submarines from receiving effective training in avoiding and overcoming enemy anti-submarine forces, which reduced then their operational capabilities once deployed. The combination of all these factors meant that the Italian submariners commenced the war with outmoded doctrine, archaic tactics, incomplete training, and a chivalric mindset unsuited to their role in the Axis anti-shipping campaign.


While Italy pursued a parallel war strategy with distinctly separate aims to Germany, Axis Submarine Forces were quickly integrated through the establishment of a regional U-Boat headquarters in Rome. In broad terms the outcomes of this arrangement were de confliction of submarine deployment and a generic understanding of operational matters. However, relations were not smooth and distrust existed to the point that German personnel were not initially allowed in the main operations room, though trust grew from necessity as Germany had substantially greater involvement in the Mediterranean. German liaison officers were also appointed to the Italian submarine facility in Bordeaux, though the facilities remained separate and not integrated to maintain clear national chains of command and logistic support. In this respect, Submarine Forces appear to have been the best aligned Axis capabilities at this stage of the war, though this was only at a broad level due to procedural incompatibility. Crucially, if liaison officers had been assigned at lower levels (such as at the Squadron level, or even assigned temporarily to individual submarines) this would likely have helped overcome some of the tactical differences that generated operational inefficiencies.

As outlined earlier, Italian submarines operated in widely dispersed theatres though this was not always coordinated effectively with the Germans. Specifically, boats operated in the Atlantic, starting from declaration of hostilities and including transfers to Bordeaux after the French surrender. However, by late 1941 German U-boats were being transferred to the Mediter-ranean to reinforce Axis naval support to the North African campaign. Admiral Doenitz opposed the redeployment of German submarines away from his Atlantic schwerpunkt, but Hitler overruled him to support the strategic situation of his Italian allies and the beleaguered Panzerarmee Afrika. The result was Italian submarines operating in the Atlantic to reinforce a German U-boat force which itself was now depleted due to transfers to the Mediterranean where the Italians had originated. This strategic confusion was not conducive to an effective interdiction and anti-commerce campaign.

Technical Issues

Unlike more iterative German U-boat designs, Italian submarine classes varied significantly, incorporating different design concepts and complicating crew training and logistical requirements. Notable differences include using two different sizes of torpedoes (the larger, more standard size for use against armored warships, and a smaller caliber torpedo for use against merchant vessels), large caliber deck guns (some classes even having dual fore and aft mounts), and a characteristically large conning tower. This latter feature made the Italian boats easier to detect on the surface both visually and through greater radar signature. Other shortcomings included shorter periscope heights in comparison to German designs, a lack of diesel intake masts which impacted rough seas operations, and rudimentary fire control apparatus which reduced torpedo accuracy. More critically for survival, Italian submarines were not optimized for crash dives, making them more susceptible to aircraft attack.

Creditably, the Italians learned the operational lessons of these shortcomings quickly and made significant efforts to rectify them. However, industrial shortcomings and competing priorities at the national level made this problem impossible to remedy completely. Technical assistance from Germany was hastily improved including the provision of electric torpedoes (which left no bubble wake like the Italian steam torpedoes, making the submarine’s attack less visible by day) and radar detection equipment to help avoid Allied aircraft. However, by early 1943 the Italian boats were deemed obsolete and relegated to non-combat resupply missions to Japan. The Kriegsmarine replaced them by gifting the Italians with seven modern German built U-boats along with appropriate training and while these were delivered, the Italian armistice occurred before any became operational. Thus, the Italians entered the war with designs that were not effective and despite later German assistance, were unable to rectify the deficiencies during the course of the war.

Comparison to Contemporary Maritime Operations

The Italians’ hard-learned lessons in a combined environment have continuing relevance for contemporary operations. In this respect, the Axis forces in 1940 were unlike modern alliances such as the North Atlantic Treaty Organization (NATO) or the Australia-New Zealand-United States Security Treaty (ANZUS), and bear greater similarity to looser organizations such as the Combined Maritime Force (CMF) in the Middle East or the Five Power Defense Agreement (FPDA). Nevertheless, there is clearly a large differential between CMF’s constabulary focused operations, the baseline warfare practices of FPDA exercises, and high-end war fighting such as the Axis anti-shipping campaign in WWII and for which NATO has trained for decades. Practiced training and doctrine, effective integration, and shared technical capabilities are only possible within an environment of closely Allied nations.The US and UK managed to achieve this effectively during WWII despite not having a close alliance prior to the war, reflecting political will and strategic relationships at the highest levels. Italy and Germany did not have this relationship, and neither do many partnership arrangements today. Differences in national commitments to an alliance can be significant with the additional demands placed by contemporary legal and domestic public issues making the differences larger and harder to overcome. In the face of these complexities, it may be difficult to resolve the political aspects of integration that generated operational challenges such as those faced by Italy and Germany from 1940-43.

In general, countries conduct their own mission preparation training before assigning a platform to a multilateral operation, with integration training restricted to basicmaneuvers and communications. A notable exception is the UK’s Flag Officer Sea Training, which conducts training off the south coast of the UK, though this is only for NATO forces and some closely aligned nations.40The utility of shared training, procedures, and doctrine cannot be overstated but require san extended period of close relations to develop.Italy and Germany did not have sufficient time prior to hostilities to do this, but neither do they appear to have prioritized a comprehensive rectification plan when these shortcomings were identified in 1940. Clearly, developing tactics, common procedures and most of all trust prior to a conflict is the optimal method for generating capability and reducing operational risk. Phase zero engagement and training exercises are, therefore, pivotal to future interoperability in a combined environment and must be prioritized accordingly.

The utility and effectiveness of placing liaison officers to enhance integration and interoperability is understood in any modern coalition or alliance model and is usually standard practice.41In this respect, through the combined Axis submarine HQ in Rome and shared facilities in Bordeaux, German-Italian Submarine Forces led the Axis powers in cooperation and coordination. From 1942 onwards, technological cooperation between Italy and Germany substantially increased to include transfer of radar detection equipment, torpedo technology, and indeed entire platforms. However, such technical exchanges today are relatively rare except where a pre-existing close relationship exists.42Similarly, coalition support provides logistic items such as food and fuel but rarely extends to critical systems and weapons, again excepting where pre-existing alliance relationships exist. Thus, many of the challenges facing the Italians and Germans in 1940 remain pertinent today.

Finally, the German-Italian experience has enduring lessons for service pride and national chain of command outside of and sometimes despite alliance priorities. Partner nations can only be as close as the political will allows, and governments will always maintain control of their own forces, which limits cooperation to some extent. As much as Germany and Italy were formally allied, they were partners of convenience thrust together at the brink of war without adequate opportunity to coordinate force development and utilization effectively. Axis submarine force difficulties were, therefore, the operational consequences resulting from divergent political aims, policies, and strategies. This continues to be a strong consideration in contemporary operations.


Italy’s entry into the war found her operating with a new ally without the opportunity to develop the baseline enabling capabilities for combined operations. This minimized the impact of tripling the available submarine platforms for the combined offensive against Allied merchant shipping. While the Italian boats were technically less advanced and more vulnerable than the Germans, mismatched doctrine and procedures made them largely ineffective even in supporting and ancillary functions.

Integrated training and common procedures remain crucial to operational effectiveness and develop with trust over an extended period. Italy and Germany did not have this time but, more critically, they did not prioritize rectification when these shortcomings were identified in 1940. It is contradictory that Doenitz implored his High Command for additional reconnaissance and strike assets, yet discarded the opportunity to develop the Italians’ potential. Instead, he largely dismissed them after his initial disappointment and did not develop their capabilities more fully. While this would admittedly have pressured Kriegsmarine training resources, this critical error had possibly decisive results. Had the reformation of Italian submarine capabilities been prioritized, Axis naval cooperation would have been much more effective at the exact time that the U-boat offensive was at its most potent and prior to the US entering the war. While this may not have affected the material superiority that the Allies later generated, it may have had a decisive impact on strategic decision making when Britain stood alone.

In other areas, Axis naval forces showed great innovation, such as combined HQ and shared facilities. Furthermore, from 1942 onwards the submarine technological cooperation between Italy and Germany was substantial. However, by the time this began in earnest the Allies, now significantly reinforced by the US, had made substantial technical and procedural improvements. For the Axis it was a case of too little, too late.

While these shortcomings are evident in hindsight, it appears that the Germans and Italians made the best of a situation plagued with political and operational constraints. Many of those same constraints exist today in loose coalitions but less so in tighter alliances such as NATO. Contemporary operations are also likely to be fast-paced, high-intensity campaigns without the years that the Axis forces had to start addressing their shortfalls.Many of the Italian lessons therefore remain eminently applicable today and need to be addressed prior to conflict where possible. Where this is not feasible, the Germans provide a solution through their efforts to identify operational areas of reduced risk to enable the Italians to best contribute within their modest level of capability. This is a valuable lesson in enabling less able partner nations to contribute operationally and potentially deliver a much greater strategic effect through their presence and integration in the combined force.


The more navies operate and exercise together prior to conflict, when mistakes and errors are far less costly, the greater their capability to operate together in future operations. To achieve the integration and procedural commonality desired, close and well-practiced alliances are the only realistic option for building effective, high-end warfare capabilities. It is therefore worth considering if there are sufficiently robust training activities, underpinned by shared enabling capabilities, technologies and relationships, focused in the regions most likely to require them. The Germans and Italians operated together only as allies of convenience and paid the price in blood and defeat. Their lack of commondoctrine and interoperability, coupled with a lack of focused effort to resolve these shortfalls when identified, cost lives and lost opportunities. Had the requisite effort been made in 1940, or prior, the potential strengthening of the U-Boat offensive in 1941 might have had decisive effects.


VADM Albert J. Baciocco, USN, Ret.
CAPT Charles B. Bishop, USN, Ret.
Dr. Frank P. Craven
STCM (SS) David L. Dalke, USN, Ret.
Mr. John D.Duncan
CAPT Richard J. Dzikowski, USN, Ret.
CAPT John Howland, USN, Ret.
Mr. Phillip L. Marshall
Mr. Don E. Messner
IC1 (SS) Alfred J. Murphy, USN, Ret.
EMCM W. David Parmenter, USN, Ret.
Mr. William E. Patterson, Sr.
CAPT Robert D. Rawlins, USN, Ret.
CAPT Charles W. Rush, USN, Ret.
CWO4 T. J. Smith, USN, Ret.
CDR William J. Traynor, USN, Ret
VADM Joe Williams, Jr., USN, Ret.

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