April 1944
| 4 | April | -General De Gaulle assumed command of all French forces. -A Greek brigade mutinied in Egypt. |
| 20/21 | April | First use and failure of German human torpedoes (Neger) at Anzio. |
| 23 | April | Greek sailors mutinied in Alexandria. |
Italian submarine patrols in the Mediterranean during April 1944
| Nichelio (…3 April) | Platino (20-27 April) | Nichelio (21-25 April) |
On 17 April 1944, the British Admiralty and Admiral Ernest J. King (COMINCH or Commander-in-Chief of the U.S. Fleet) concluded an agreement dividing, between themselves, Italian submarines used for training duties. Initially, Goffredo Mameli was allocated to the Americans, Giada, Benedetto Brin, and Filippo Corridoni to the British. It was also agreed that Onice and Giovanni Da Procida would be the next ones to be given to the Americans as soon as they had completed their refit. The remainder would be divided equally, the first available to the British. The eleven submarines not yet allocated were Atropo, Fratelli Bandiera, Ammiraglio Cagni, Diaspro, Jalea, Ciro Menotti, Nichelio, Otaria, Platino, Luigi Settembrini, and Ruggiero Settimo. Because of their odd number, this meant that six would go to the British and five to the Americans. Italian submariners were probably unaware of the hard bargaining they were the object of. On 18 December 1944, the British informed the Americans that they considered that three submarines had already been allocated before the agreement of 17 April had come into effect. These were Fratelli Bandiera and Jalea to the British(the latter taking the place of Giada, who had a broken crankshaft and was still out of action) and Giovanni Da Procida, who had gone to the Americans instead of Jalea, The first three boats available after the equal share had come into effect were Atropo and Settembrini to the Americans and Menotti to the British. The second group of three available thus had one for the Americans (Diaspro) and two for the British (Platino and Nichelio).
Since it was recognised that Settembrini had been lost before assuming her duties, the British were ready to offer Zoea instead before the division of the spoils continued. In fact, Italian submarines were judged essential for both Allies. The sudden growth of their respective escort vessel forces had put a great strain on their capacities to train them, and they were reluctant to divert some of their own submarine resources for the task. Their old submarines were no longer up to the task, and their newly built submarines were too valuable for their offensive value. Eventually, Dandolo was also part of the deal.
Mediterranean
On the first of the month, Giada (T.V. Mario Barazzuoli) sailed from Augusta for Colombo, where she was to be used for anti-submarine exercises. On 15 April, Benedetto Brin (T.V. Carlo Imperiali) sailed from Malta for the same destination.
Nichelio (T.V. Ugo Esmenard) landed three Greek agents of Force 133 (SOE) on the island of Zante during the night of 22/23 April. The following night, it was the turn of Platino (T.V. Vittorio Patrelli Campagnano) to land a group of agents near Cortelazzo. This was Special Operation ACORN/LEEDS.
On 20 April, the large transport submarine UI 5 (ex-R.8) and the midget C.B.15, presently under German control, were sunk by sixty-four Liberators during a raid on Monfalcone.