The Regia Marina (RM) or Royal Italian Navy was the navy of the Kingdom of Italy from 1861 to 1946. In 1946, with the birth of the Italian Republic, the Regia Marina changed its name to Marina Militare.
The Freccia-class destroyer was a class of destroyers built for the Regia Marina in the 1930s. Four modified ships were built and delivered in 1933 for Greece.
At the outbreak of the Second World War Nazi Germany's Kriegsmarine had 21 destroyers in service, while another one was just being completed. These 22 vessels – comprising 3 classes – had all been built in the 1930s, making them modern vessels. Including that final pre-war vessel, a further 19 were brought into service during the war and more were captured from opposing navies, including the Italian Navy after the Italian Armistice with the Allies in 1943.
The Spica class were a class of torpedo boats of the Regia Marina during World War II. These ships were built as a result of a clause in the Washington Naval Treaty, which stated that ships with a tonnage of less than 600 could be built in unlimited numbers. Thirty-two ships were built between 1934 and 1937, thirty of which entered service with Italy and two of which were sold to the Swedish Navy in 1940. The two units in Swedish service were classified as destroyers until 1953, then re-classified as corvettes. Although commonly referred to as torpedo boats due to their smaller displacement, the Spica class armaments were similar in design to destroyers and were intended for anti-submarine duties, although they often had to fight aircraft and surface forces as well. Twenty-three vessels were lost during World War II.
The Navigatori class were a group of Italian destroyers built in 1928–1929 for the Regia Marina, named after Italian explorers. They fought in World War II. Just one vessel, Nicoloso Da Recco, survived the conflict.
The Folgore class were a group of four destroyers built for the Regia Marina in the 1930s. None of the ships survived World War II.
The Sella-class destroyers were a group of four destroyers built for the Regia Marina in the 1920s. Two of these ships fought in World War II and both were sunk after the Italian capitulation to the Allies. The two other ships were sold to the Swedish Navy in 1940 and were scrapped in the late 1940s.
The Orsa class were a group of large torpedo boats or destroyer escorts built for the Italian Navy in the late 1930s. They were an enlarged version of the Spica-class torpedo boat, specifically tailored for the escort and anti-submarine role, with greater endurance and a heavier depth charge armament but less powerful machinery and a lighter gun armament. Four were built, with two being lost during the Second World War. The surviving pair were rebuilt as anti-submarine frigates in the 1950s.
The Ariete-class torpedo boats were a group of destroyer escorts built for the Italian Navy during World War II. They were enlarged versions of the Spica-class torpedo boats and designed to escort convoys to North Africa. Of the 42 units planned, sixteen ships were eventually ordered but only one was completed by the time of the armistice, Ariete, built in the Sestri Ponente shipyards and commissioned on 5 August 1943. The namesake ship was also the only one to survive the war. After the war it was ceded to the Yugoslav Navy (1949), and renamed Durmitor.
Dubrovnik was a flotilla leader built for the Royal Yugoslav Navy by Yarrow Shipbuilders in Glasgow in 1930 and 1931. She was one of the largest destroyers of her time. Resembling contemporary British designs, Dubrovnik was a fast ship with a main armament of four Czechoslovak-built Škoda 140 mm (5.5 in) guns in single mounts. She was intended to be the first of three flotilla leaders built for Yugoslavia, but was the only one completed. During her service with the Royal Yugoslav Navy, Dubrovnik undertook several peacetime cruises through the Mediterranean, the Turkish Straits and the Black Sea. In October 1934, she conveyed King Alexander to France for a state visit, and carried his body back to Yugoslavia following his assassination in Marseille.
The Alpino class were a group of two frigates built for the Italian Navy during the Cold War.
HSwMS Puke (19) was a Psilander-class destroyer of the Swedish Navy from 1940 to 1947. The ship was purchased from Italy by Sweden in 1940, along with her sister ship HSwMS Psilander. Before that, she served in the Regia Marina as Bettino Ricasoli, one of four members of the Italian Sella class. Puke was scrapped in 1949.
HSwMS Remus (28) was a Romulus-class destroyer of the Royal Swedish Navy during World War II. She had been built as Astore, a Spica-class torpedo boat for Italy's Regia Marina, in the mid-1930s and sold to Sweden in 1940. She was stricken in 1958 and scrapped in 1961.
Nicoloso da Recco was one of a dozen Navigatori-class destroyers built for the Regia Marina in 1930. Named after the Italian Renaissance seaman Nicoloso da Recco, she served during World War II in which she was the sole survivor of her destroyer class. She shot down three Beaufort bombers while escorting a two-freighter convoy on 21 June 1942 off Tunisia. On 2 December 1942 Nicoloso Da Recco took part of the Battle of Skerki Bank, where an Italo-German convoy carrying troops and supplies to Libya was obliterated by Allied naval forces. Nicoloso Da Recco was the only vessel of her class to survive the war, and was eventually scrapped in July 1954.
The Romulus class was a class of two destroyers operated by the Royal Swedish Navy during the Second World War. The class consisted of HSwMS Romulus and HSwMS Remus. They were built in Italy as the Spica-class torpedo boats Spica and Astore in the mid-1930s and sold to Sweden in 1940. The two ships were adapted for northern conditions and remained in service during World War II and into the first decades of the Cold War. They were modernized and re-designated as anti-submarine frigates in 1953. Both ships were discarded in 1958.
HMS Pakenham (G06) was a P-class destroyer of the British Royal Navy built and operated during World War II. Commissioned in early 1942, she took part in the invasion of Madagascar, and several Malta Convoys, before being disabled in a battle with Italian torpedo boats in April 1943 and scuttled.
The Italian torpedo boat Lupo was a Spica-class torpedo boat built for the Regia Marina in the late 1930s. During the Second World War, Lupo was involved in several naval actions, including that of the eponymous "Lupo convoy", for which she was awarded the Silver Medal of Military Valour. Lupo was sunk in action on 2 December 1942.
HSwMS Psilander (18) was a Psilander-class destroyer of the Swedish Navy from 1940 to 1947. The ship was purchased from Italy by Sweden in 1940, along with her sister ship HSwMS Puke. Before that, she served in the Regia Marina as Giovanni Nicotera, one of four members of the Italian Sella class. Psilander was scrapped in 1949.
Alfredo Oriani was the lead ship of her class of four destroyers built for the Regia Marina in the mid-1930s. Completed in 1937, she served in World War II. Alfredo Oriani took part of the battle of Matapan and the attack on Harpoon convoy.
The Aldebaran class was a class of three frigates/corvettes/destroyer escorts operated by the Italian Navy. They entered service in 1951, with the last one being decommissioned in 1976.
Italy 
Sweden 
