U-Boats - The Italian Connection
by Derek Waller
During the first half of WW2 there was close co-operation between the submarine arms of the German and Italian navies, and there are three separate, but connected, elements to the story of the Italian U-Boats.
First, seven large Italian submarines were based in Bordeaux from where, in conjunction with the Kriegsmarine, they undertook anti-shipping patrols in the Atlantic. However, early in 1943, the German and Italian Navies decided that, since these submarines were not suitable for commerce raiding, they would be of more use if they were converted into transport submarines for ferrying equipment and raw materials to and from Japanese sources in the Far East. At this stage of the war surface traffic between Japan and the Axis powers was becoming increasingly difficult due to the efficiency of the Allied blockade, but it was still essential to both the Germans and the Japanese that, in particular, they exchanged strategic raw materials.
As a result, it was decided that the Italian Navy would hand over these seven large submarines to the Kriegsmarine, even though they were manned and commanded by Italians, and in return the latter undertook to supply the Italian Navy with 10 new, but smaller, type VIIC German U-Boats.
The seven Italian submarines were therefore converted into cargo carriers for the Far East run and, by the end of June 1943, five of them had been converted and had sailed from Bordeaux. However, only three reached their destination; the other two being lost on passage. The remaining two had not sailed by the time of the Italian surrender to the Allies.
| Cappellini | Sailed - 11 May 1943 |
| Tazzoli | Sailed - 16 May 1943 (sunk on passage on 22 May 1943) |
| Guiliani | Sailed - 23 May 1943 |
| Torelli | Sailed - 14 June 1943 |
| Barbarigo | Sailed - 15 June 1943 (sunk on passage on 19 June 1943) |
| Bagnolini | - |
| Frinzi | - |
When the Italian Armistice was declared on 8 September 1943, Cappellini was in Sabang (Sumatra), Guiliani and Torelli were in Singapore, and Bagnolini and Frinzi were still in Bordeaux undergoing conversion. All five were then taken over by the Kriegsmarine and given U-Boat designations:
| Cappellini | U-IT-24 |
| Guiliani | U-IT-23 |
| Torelli | U-IT-25 |
| Bagnolini | U-IT-22 |
| Frinzi | U-IT-21 |
Subsequently, U-IT-21 was scrapped when the Germans withdrew from Bordeaux in August 1944, and U-IT-22 and U-IT-23 were lost at sea. U-IT-24 and U-IT-25 (both of which had been taken over by the Japanese Navy in May 1945) surrendered in Kobe, Japan in August 1945. They were then captured in the Kobe shipyards by US forces in September 1945, and subsequently sunk by the US Navy on 16 April 1946 in the Kii Suido between the Japanese islands of Honshu and Shikolu.
The second element of the story relates to the 10 type VIIC German U-Boats which the Kriegsmarine undertook to supply to the Italian Navy in exchange for the seven larger (transport) submarines.
The first of these U-Boats (S1 - ex U-428) was handed over to the Italian Navy on 26 June 1943 in Danzig, where trials and training were carried out prior to its planned move to an Atlantic base. However, when the Italian Armistice was declared in September 1943, although nine of the 10 U-Boats had actually been handed over to the Italians, none had been moved from the Baltic, and they were therefore all taken back into the Kriegsmarine on 9 September 1943 retaining their original U-Boat numbers.
The 10 U-Boats were:
| U-428 | (Italian S1) | To Italian Navy - 26 June 1943 |
| U-429 | (Italian S4) | To Italian Navy - 14 July 1943 |
| U-430 | (Italian S6) | To Italian Navy - 4 August 1943 |
| U-746 | (Italian S2) | To Italian Navy - 4 July 1943 |
| U-747 | (Italian S3) | To Italian Navy - 18 July 1943 |
| U-748 | (Italian S5) | To Italian Navy - 31 July 1943 |
| U-749 | (Italian S7) | To Italian Navy - 14 August 1943 |
| U-750 | (Italian S9) | To Italian Navy - 26 August 1943 |
| U-1161 | (Italian S8) | To Italian Navy - 25 August 1943 |
| U-1162 | (Italian S10) | Not handed over |
Subsequently, these 10 U-boats were used for training purposes in the Baltic, where four were sunk in USAAF air raids in 1945, and where the remaining six were scuttled by their crews rather than surrender in May 1945.
The third element of the story relates to the other 25 Italian submarines which were taken over by Germany in September 1943 after the Italian Armistice. Although 20 of these submarines were allocated U-IT numbers by the Kriegsmarine, most had been unfinished when they were captured in September 1943, and none were ever either formally commissioned into the Kriegsmarine or used in action.
Indeed, there is some debate between historians as to whether or not they were all even formally allocated U-IT numbers. I have assumed that since the U-IT sequence definitely started with U-IT-1, and since it definitely included U-IT-21 to U-IT-25, it is illogical to believe that the sequence was broken. However, by the end of the war, with the one exception of the midget submarine CM1 (U-IT-17), all 20 of them had either been damaged or sunk in air attacks or had been scuttled in early May 1945.
| U-IT-1 | R10. Captured in unfinished state at La Spezia 9 September 1943. Launched 12 July 1944 and transferred to Genoa. Sunk in Genoa on 4 September 1944 in RAF air raid. Raised in 1946 and broken-up in 1947. |
| U-IT-2 | R11. Captured in unfinished state at La Spezia 9 September 1943. Launched 6 July 1944 and transferred to Genoa. Scuttled Genoa 24 April 1945 after RAF air raid. Refloated in 1946. Employed as floating oil tank GR.522. |
| U-IT-3 | R12. Captured in unfinished state at La Spezia 9 September 1943. Launched 29 September 44. Scuttled La Spezia 24 April 1945. Refloated in 1946. Employed as floating oil tank GR.523. |
| U-IT-4 | R7. Captured in unfinished state at Monfalcone 9 September 1943. Sunk in USAAF air raid on Monfalcone 25 May 1944. Raised on 31 May 1946 and broken-up in 1948. |
| U-IT-5 | R8. Captured in unfinished state at Monfalcone 9 September 1943. Launched 28 December 1943. Sunk in USAAF air raid on Monfalcone 20 April 1944. Raised on 3 June 1946 and broken-up in 1947. |
| U-IT-6 | R9. Captured in unfinished state at Monfalcone 9 September 1943. Construction suspended and laid-up 5 September 1944. Sunk 16 March 1945 in RAF air raid. Raised in June 1946, and broken-up in 1948. |
| U-IT-7 | Bario. Captured in unfinished state at Monfalcone 9 September 1943. Launched 23 January 1944. Damaged in air raid on Monfalcone 16 March 1945. Scuttled 1 May 1945. Raised in 1945. Reconditioned 1953/55 in Taranto. Reconstructed and modernised 1957/59. Relaunched as the Italian Navy submarine Bario on 21 June 1959. Name changed to Pietro Calvi and commissioned into the Italian Navy on 16 December 1961. It was then used for training until it was laid up in 1971, and it was finally discarded in April 1973. |
| U-IT-8 | Litio. Captured in unfinished state at Monfalcone 9 September 1943. Damaged in air raid on Monfalcone 16 March 1945. Scuttled 1 May 1945. Later raised and towed to Taranto. Then scrapped. |
| U-IT-9 | Sodio. Captured in unfinished state at Monfalcone 9 September 1943. Damaged in air raid on Monfalcone 16 March 1945. Scuttled 1 May 1945. |
| U-IT-10 | Potassio. Captured in unfinished state at Monfalcone 9 September 1943. Blown up on slip 1 May 1945. |
| U-IT-11 | Rame. Captured in unfinished state at Monfalcone 9 September 1943. Blown up on slip 1 May 1945. |
| U-IT-12 | Ferro. Captured in unfinished state at Monfalcone 9 September 1943. Blown up on slip 1 May 1945. |
| U-IT-13 | Piombo. Captured in unfinished state at Monfalcone 9 September 1943. Blown up on slip 1 May 1945. |
| U-IT-14 | Zinco. Captured in unfinished state at Monfalcone 9 September 1943. Blown up on slip 1 May 1945. |
| U-IT-15 | Sparide. Scuttled by Italians at La Spezia on 9 September 1943, but then raised. Sunk in RAF air raid on Genoa on 4 September 1944. Raised and broken up 27 March 1947. |
| U-IT-16 | Murena. Scuttled by Italians at La Spezia on 9 September 1943, but then raised. Sunk in RAF air raid on Genoa on 4 September 1944. Raised and broken up 27 March 1947. |
| U-IT-17 | CM1 (92 ton midget s/m). Captured in Monfalcone on 9 September 1943. Transferred to the Italian Fascist Navy and completed on 4 January 1945. Taken over a partisan crew and moved south to re-join the R Italian Navy in April 1945. Discarded on 1 February 1948, and then broken up. |
| U-IT-18 | CM2 (92 ton midget s/m). Captured in unfinished state at Monfalcone 9 September 1943. Not completed and damaged on slip in USAAF air raid on 25 May 1944. Scuttled on 1 May 1945. Refloated in October 1950, and transferred to the Naval Museum at Trieste in 1951 - where it was on display for several years. |
| U-IT-19 | Nautilo. Scuttled by Italians at Venice on 9 September 1943, but then raised. Sunk in RAF air raid on Pola, Yugoslavia (but then in Italy) on 9 January 1944. Raised and commissioned into the Yugoslav Navy as P802 Sava. Withdrawn from service in 1968. |
| U-IT-20 | Grongo. Scuttled by Italians at La Spezia on 9 September 1943, but then raised. Sunk in RAF air raid on Genoa on 4 September 1944. |
The five other Italian submarines which came under German control in northern Italian ports on 9 September 1943, none of which were allocated U-IT numbers as a possible prelude to commissioning in the Kriegsmarine, were:
| Ambra | Scuttled by Italians at La Spezia on 9 September 1943, and then raised. Sunk in RAF air raid on Genoa on 4 September 1944. |
| Aradam | Scuttled by Italians at Genoa on 9 September 1943, and then raised. Sunk in RAF air raid on Genoa on 4 September 1944. |
| Argo | Scuttled by Italians at Monfalcone on 9 September 1943, and the raised. Broken up as beyond repair. |
| Volframio | Scuttled by Italians at La Spezia on 9 September 1943, and then raised. Sunk in air raid on La Spezia in 1944. |
| Beilul | Captured at Monfalcone while under repair on 9 September 1943. Sunk in RAF air raid on Monfalcone on 25 May 1944. |
Footnote
Much of my original information about these Italian submarines/U-Boats was obtained in 1966 and 1967 during correspondence with the late Aldo Fraccaroli. This was well before the invention of the Internet and the availability of so much more information, albeit that - after all the intervening years - there is still some uncertainty as to exactly what happened to many of these Italian submarines after the Italian armistice was announced on 8 September 1943. Also, I commend readers to Janes Fighting Ships 1946-47 (which included the official war losses list) and to Janes Fighting Ships 1950-51 (which included an Italian Navy Supplement).
This article was published on 18 Nov 2010.