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 during her voyage to Russia carrying British Secretary of State for War Lord Kitchener. The cruiser sank at 59.1167°N -27°W west of the Orkney Islands with nearly total loss of life in a force 9 gale.
Type UE I submarines were preceded by the longer Type U 66 submarines. U-75 had a displacement of 755t when at the surface and 832t while submerged. She had a total length of 56.8m (186.4feet), a pressure hull length of 46.66m (153.08feet), a beam of 5.9m (19.4feet), a height of 8.25m (27.07feet), and a draught of 4.86m (15.94feet). The submarine was powered by two 900PS engines for use while surfaced, and two 800PS engines for use while submerged. She had two propeller shafts. She was capable of operating at depths of up to .
The submarine had a maximum surface speed of and a maximum submerged speed of . When submerged, she could operate for at ; when surfaced, she could travel at . U-75 was fitted with two torpedo tubes (one at the port bow and one starboard stern), four torpedoes, and one 8.8sp=usNaNsp=us SK L/30 deck gun. She had a complement of thirty-two (twenty-eight crew members and four officers).
| Date | Name | Nationality | Tonnage[1] | Fate[2] | |
|---|---|---|---|---|---|
| 5 June 1916 | 10,850 | Sunk | |||
| 22 June 1916 | HMD Laurel Crown | 81 | Sunk | ||
| 7 August 1916 | HMT John High | 228 | Sunk | ||
| 12 August 1916 | Kovda | 1,125 | Sunk | ||
| 20 September 1916 | Etton |  United Kingdom | 2,831 | Sunk | |
| 16 November 1916 | Fenja |  Denmark | 433 | Sunk | |
| 22 November 1916 | Reserv |  Sweden | 1,700 | Captured as prize | |
| 23 November 1916 | Arthur | Sweden | 1,435 | Sunk | |
| 9 April 1917 | Ganslei | 1,273 | Sunk | ||
| 15 April 1917 | HMT Arctic Prince | 194 | Damaged | ||
| 10 August 1917 | Solglimt |  Norway | 1,037 | Sunk | |
| 16 August 1917 | Palatine | United Kingdom | 2,110 | Sunk | |
| 3 September 1917 | Treverbyn | United Kingdom | 4,163 | Sunk | |
| 22 November 1917 | King Idwal | United Kingdom | 3,631 | Sunk | |
| 10 December 1917 | Aureole | United Kingdom | 3,998 | Damaged | |
| 2 September 1918 | Ariadne Christine | United Kingdom | 3,550 | Damaged |