HMS Umbra (P35) was a Royal Navy U-class submarine built by Vickers-Armstrongs at Barrow-in-Furness. So far she has been the only ship of the Royal Navy to bear the name Umbra.
Jun'yō Maru (順陽丸) was a cargo steamship that was built in Scotland in 1913, served a succession of British owners until 1927, and was then in Japanese ownership until a Royal Navy submarine sank her in 1944.
I-8 was an Imperial Japanese Navy Junsen III -type submarine commissioned in 1938 that served during World War II. Designed as submarine aircraft carriers, I-8 and her sister ship I-7 were the largest Japanese submarines to be completed before the outbreak of the war in the Pacific in 1941. With embarked floatplanes, I-8 participated in operations related to the attack on Pearl Harbor, patrolled off the United States West Coast, and took part in the Guadalcanal campaign and the Okinawa campaign.
Chūyō was a Taiyō-class escort carrier originally built as Nitta Maru, the first of her class of three passenger-cargo liners built in Japan during the late 1930s. She was requisitioned by the Imperial Japanese Navy (IJN) in late 1941 and was converted into an escort carrier in 1942. She spent most of her service ferrying aircraft, cargo and passengers to Truk until she was torpedoed and sunk by an American submarine in late 1943 with heavy loss of life.
HMS Sahib was a third-batch S-class submarine built for the Royal Navy during the Second World War. She was launched on 19 January 1942 and commissioned on 13 May 1942. She was the only British naval vessel to bear the name Sahib.
HMS Porpoise (N14) was one of the six-ship class of Grampus-class mine-laying submarines of the Royal Navy. She was built at Vickers Armstrong, Barrow and launched 30 August 1932. She served in World War II in most of the naval theatres of the war, in home waters, the Mediterranean and the Far East. She was sunk with all hands by Japanese aircraft on 19 January 1945, and was the last Royal Navy submarine to be lost to enemy action.
HMS Torbay (N79) was a T-class submarine of the Royal Navy. She was laid down at Chatham Dockyard and launched on 9 April 1940.
HMS Turbulent (N98) was a T-class submarine of the Royal Navy. She was laid down by Vickers Armstrong, Barrow and launched in May 1941.
Shin'yō Maru was a cargo steamship that was built in 1894, had a fifty-year career under successive British, Australian, Chinese and Greek owners, was captured by Japan in the Second World War, and sunk by a United States Navy submarine in 1944.
SM U-4 or U-IV was a U-3-class submarine or U-boat built for and operated by the Austro-Hungarian Navy before and during the First World War. The submarine was built as part of a plan to evaluate foreign submarine designs, and was the second of two boats of the class built by Germaniawerft of Kiel, Germany.
The Shin'yō Maru incident occurred in the Philippines on September 7, 1944, in the Pacific theater of World War II. In an attack on a Japanese convoy by the United States Navy submarine USS Paddle, 668 Allied prisoners of war were killed fighting their Japanese guards or killed when their ship, Shinyō Maru, was sunk. Only 82 Americans survived and were later rescued.
SS Scillin was a 1,591 GRT cargo steamship that was built in Scotland in 1903, passed through a succession of owners of various nationalities and had a succession of different names. She was built as H. M. Pellatt but was successively called Memling, Nicole Le Borgne, Giuliana Pagan, and Scillin Secondo before becoming Scillin in 1937.
SS Loreto, formerly Astrée, was a 1,069 GRT cargo steamship that was built in England in 1912 for French owners and bought in 1933 by Italian owners who renamed her Loreto. In 1942 a Royal Navy submarine sank her in the Tyrrhenian Sea, killing 130 British Indian Army prisoners of war who were aboard.
MV Sebastiano Veniero, formerly MV Jason, was a 6,310 GRT cargo and passenger motor ship that was built in Monfalcone, Italy in 1940. In 1941 she was damaged by a Royal Navy submarine in the Mediterranean Sea, killing at least 300 UK and Dominion prisoners of war, and possibly many more. She did not sink but was beached on the coast of the Peloponnese, where she was torpedoed again a week later and became a total loss.
The Nino Bixio class was a pair of protected cruisers built for the Italian Regia Marina in the 1910s. The two ships, Nino Bixio, and Marsala, were built in Castellammare between 1911 and 1914. They were intended to serve as scouts for the main Italian fleet, and as such required a high top speed. They were overweight as built, which prevented them from reaching their intended maximum speed. They were a disappointment in service, especially compared to the earlier—and faster—cruiser Quarto, which cut their careers short.
Nino Bixio was a protected cruiser built by the Italian Regia Marina in the early 1910s. She was the lead ship of the Nino Bixio class, which were built as scouts for the main Italian fleet. She was equipped with a main battery of six 120-millimeter (4.7 in) guns and had a top speed in excess of 26 knots, but her engines proved to be troublesome in service. Nino Bixio saw service during World War I and briefly engaged the Austro-Hungarian cruiser SMS Helgoland in 1915. Her career was cut short in the post-war period due to severe cuts to the Italian naval budget, coupled with her unreliable engines. Nino Bixio was stricken from the naval register in March 1929 and sold for scrap.
Håkon Nilsen, Stavanger, Norway, popularly known as "Torpedo Nilsen", was a Norwegian war veteran and highly decorated allied naval torpedo commander of World War II.
Turbine was the lead ship of her class of eight destroyers built for the Regia Marina during the 1920s. Her name means whirlwind.
Pegaso was a torpedo boat and an escort aviso of the Italian Regia Marina. She was one of the most successful Axis anti-submarine warships of World War II.
