Royal Italian Submarines in the Atlantic

Despite having built a sizable fleet of oceanic submariners, the Italian command had failed to properly analyze the implications surrounding the crossing of the Strait of Gibraltar, a narrow at the western end of the Mediterranean heavily guarded by the British Navy. The first three submarines sent to the Atlantic, the Malaspina , Barbarigo and Dandolo , crossed the strait in August 1940 without incident, sank a total of 13,593 tons, and since the submarine base of Betasom had just become operative, instead of returning to Italy, were rerouted to Bordeaux. In the subsequent weeks, a total of 27 Italian submarines crossed the strait with only one unit, the Bianchi, being damaged by a British patrol . Before reaching Bordeaux, these submarines were deployed west of the Strait of Gibraltar, achieving some negligible results. It was indicative that the first group sent to the Atlantic included also the Tazzoli , Cappellini , and Glauco, but none of these boats was even able to reach the Strait of Gibraltar due to technical failures. Failures would plague Italian submarines throughout the conflict, but while diesel engines, pumps, and other equipment often failed, weaponry (deck guns and torpedoes) was in general quite reliable.

Soon after, a new group of submarines including the Emo, Faà di Bruno, Giuliani, Tarantini, Torelli, and Baracca left Italian bases for the Atlantic. A third group, including the Marconi, Finzi and Bagnolini, left in early September, a fourth group including the Da Vinci and Otaria crossed the Strait of Gibraltar at the end of September, and a fifth group including the Glauco, Veniero, Nani, Cappellini, Calvi, Tazzoli, and the Argo the following new moon. To avoid detection, after the very first Italian submarine had crossed on the surface and reported on the experience, it was decided to proceed submerged and during a period of new moon. Of the new submariners, the Cappellini, would become the protagonist of an unusual event. After having sunk the freighter Kabalo , the captain would rescue the crew in an epic rescue operation , but the fight during the Battle of the Atlantic would not have room for chivalries.

On September 30th, Dönitz visited Bordeaux to arrange joint military operations . Because Hitler did not want to have German forces soon to be deployed in North Africa under Italian command, the Italian submarines in Bordeaux were officially left under Italian command. Practically, Dönitz intended to have full control of these precious submarines, and the Italian commanding officer, Rear-Admiral Parona , was ready to oblige. Fluent in German, Parona had previously translated some German military literature in the area of submarine tactics, and was a highly respected submariner.