April 1945
| 7 | April | The Japanese super battleship Yamato was sunk by American aircraft. |
| 9 | April | Bari suffered another catastrophe when the American transport Charles Henderson blew up. |
| 12 | April | Death of President Roosevelt. |
| 13 | April | The Soviet Army entered Vienna. |
| 24 | April | Allied forces entered La Spezia. |
| 28 | April | -Mussolini was captured by partisans and executed. -Allied forces occupied Genoa. |
| 30 | April | Hitler committed suicide. Grand Admiral Dönitz became the head of the German government. |
Italian (RSI) submarine patrols in the Mediterranean during April 1945
| C.B.6 (…3 April*) | C.B.18 (…6 April*) |
On 2 April, C.B.18 (G.M. Alberto Coletti), operated by the Italian Socialist Republic, landed two agents north of Pesaro. They were almost immediately captured, but the midget submarine disappeared without a trace. On 7 April, Coletti was proposed for the Iron Cross.
C.B.6 (G.M. Gabriele Battistini) was attacked with cannon fire by a Spitfire of 1435 Squadron. The midget submarine managed to submerge and escape, only to be sunk after midnight on 3 April by a Wellington of 38 Squadron. Her four crew members and two saboteurs were rescued by a Catalina.
MTB-710 on offensive patrol with MTB–697 and MTB–706, reported being missed by two torpedoes in the Arsa Channel on 6 April. This was possibly the midget submarine C.B.18, which may have been sunk in the counterattack. Four days later, MTB–710 blew up on a mine. Although another six men of the Eulenspiegel detachment were initially earmarked to be landed by midget boats in the middle of April, the task was finally entrusted to fast motorboats.
On 21 April, the German 6th K-Division again raised the question of sending a midget submarine to Leros —C.M.1 was considered— arguing that a stop could be made in Crete, which was 910 miles from Pola. Given the theoretical maximum range of 1,000 miles at six knots for these boats, this meant there was a margin of only ninety miles. It was recognized that the boats would only be able to travel by night and that the trip would take fifteen days. This was beyond the endurance of a normal crew in these cramped quarters. The end of the war removed the need to put this idea to the test.
But it was not yet the end of the war for the Italians fighting with the Allies. On the night of 17/18 April, two Italian human torpedoes brought by the Italian M.S.74 with MGB-177 and two MTSMs were launched off Genoa. The operation was led by C.V. Forza. They had sailed from Leghorn to attack the half-completed aircraft carrier Aquila as it was feared she would be used by the Germans as a block ship (Operation TOAST). One SLC, manned by G.M. Girolamo Manisco and Sottocapo palombaro (Diving Petty Officer) Dino Varini, exhausted its batteries and was abandoned, but the crew was recovered by an MTSM. The other SLC, manned by S.T.V. Nicola Conte and Sottocapo palombaro Evelino Marcolini, managed to plant its charge ten feet below the aircraft carrier’s keel. They also were recovered safely and brought back to Leghorn. However, only the anti-torpedo bulge was holed, and the aircraft carrier failed to sink. Again, some doubts were raised that Aquila was ever damaged, as witnesses did not report any explosion, and no remains of the SLC were later found.
At the end of the month, resistance in northern Italy began to collapse. Germans and die-hard fascists were preparing to destroy harbour facilities of Genoa, Venice, and others.