SM U-90 was a Type U-87 U-boat of the Imperial German Navy during World War I. Its commander Walter Remy made regular stops at remote island North Rona for provisions such as fresh mutton. On 15 May 1918, U-90 shelled the Hirta wireless station in St Kilda, Scotland. On 31 May 1918, U-90 torpedoed and sank USS President Lincoln, a former Hamburg America Line steamer that had been seized by the United States for troop transportation. From the U.S. Navy crew that abandoned the sinking vessel, U-90 captured Lieutenant Edouard Izac, eventually taking him to Germany. Izac later escaped German captivity and reported to the US Navy about German submarine movements.
SM UB-23 was a German Type UB II submarine or U-boat in the German Imperial Navy during World War I. The U-boat was ordered on 30 April 1915 and launched on 9 October 1915. She was commissioned into the Imperial German Navy on 13 March 1916 as SM UB-23. The submarine sank 51 ships in 21 patrols for a total of 33,880 gross register tons (GRT). On 26 July 1917, UB-23 was badly damaged by a depth charge attack by HMS PC-60 off the Lizard; she put in at Corunna, Spain, on 29 July 1917 and was interned. On 22 January 1919 she was surrendered to France in accordance with the requirements of the Armistice with Germany, and she was broken up in Cherbourg in July 1921.
SM UB-35 was a German Type UB II submarine or U-boat in the German Imperial Navy during World War I. The U-boat was ordered on 22 July 1915 and launched on 28 December 1915. She was commissioned into the German Imperial Navy on 22 June 1916 as SM UB-35.
SM UB-38 was a German Type UB II submarine or U-boat in the German Imperial Navy during World War I.
SM UC-17 was a German Type UC II minelaying submarine or U-boat in the Imperial German Navy in World War I. She was ordered on 29 August 1915 and launched on 29 February 1916. She was commissioned into the Imperial German Navy on 21 July 1916 as SM UC-17.
SM UC-64 was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy during World War I. The U-boat was ordered on 12 January 1916, laid down on 3 April 1916, and was launched on 23 January 1917. She was commissioned into the German Imperial Navy on 22 February 1917 as SM UC-64. In 15 patrols UC-64 was credited with sinking 26 ships, either by torpedo or by mines laid. UC-64 was mined and sunk in the Dover Strait on 20 June 1918.
SM U-34 was a German U-boat of World War I. Launched on 9 May 1914, U-34 sank a total of 119 ships during 17 combat patrols, while damaging another 5 ships. The vessel had three commanders during its time: Kptlt. Claus Rucker, Kptlt. Johannes Klasing, Kptlt. Wilhelm Canaris, and Klasing again, in that order. On 18 October 1918, U-34 sailed for the last time, disappearing with all 38 crew members lost. Although it was claimed that she was depth charged and sunk near Gibraltar by HMS Privet on 9 November 1918, it is believed that the U-boat had been lost prior to that, but it has never been confirmed one way or the other.
SM U-72 was one of 329 submarines serving in the Imperial German Navy in World War I. U-72 was engaged in the commerce war in First Battle of the Atlantic.
SM U-74 was a Type UE 1 submarine and one of the 329 submarines serving in the Imperial German Navy in World War I. U-74 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
SM U-75 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-75 was engaged in naval warfare and took part in the First Battle of the Atlantic. On her first mission, U-75 laid the mine that sank the cruiser HMS Hampshire during her voyage to Russia carrying British Secretary of State for War Lord Kitchener. The cruiser sank at 59°07′N03°24′W west of the Orkney Islands with nearly total loss of life in a force 9 gale.
SM U-76 was a Type UE 1 submarine and one of the 329 submarines serving in the Imperial German Navy in World War I. U-76 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
SM U-80 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-80 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
SM U-81 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-81 was engaged in naval warfare and took part in the First Battle of the Atlantic.
SM U-84 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-84 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
SM U-87 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-87 was engaged in the naval warfare and took part in the First Battle of the Atlantic. She sank some 22 merchant vessels before 25 December 1917, when HMS Buttercup rammed U-87 in the Irish Sea and depth-charged her. Then the P-class sloop P.56 sank her. U-87's entire crew of 44 were lost.
SM U-88 was a Type U 87 submarine built for the Imperial German Navy in World War I. U-88 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
SM U-89 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-89 was engaged in the naval warfare and took part in the First Battle of the Atlantic. On 12 February 1918, U-89 was rammed and sunk by HMS Roxburgh off Malin Head. There were no survivors.
SM U-97 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-97 was engaged in the naval warfare and took part in the First Battle of the Atlantic. The German unit sank by accident on her way to surrender at position 53°25′N3°10′E.
SM U-98 was a Type U 93 submarine and one of the 329 submarines serving in the Imperial German Navy in World War I. U-98 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
SM U-107 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-107 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
German Empire 
