SMS Karlsruhe (1916)

Operations of the German Navy and Army during Operation Albion

In early September 1917, following the German conquest of the Russian port of Riga, the German navy decided to eliminate the Russian naval forces that still held the Gulf of Riga. Karlsruhe took part in training exercises that month with the rest of II Scouting Group in preparation for the attack. The Admiralstab (Navy High Command) planned Operation Albion to seize the Baltic island of Ösel, and specifically the Russian gun batteries on the Sworbe Peninsula. On 18 September, the order was issued for a joint operation with the army to capture Ösel and Moon Islands; the primary naval component comprised the flagship, the battlecruiser Moltke, along with the III and IV Battle Squadrons of the High Seas Fleet. The invasion force amounted to approximately 24,600 officers and enlisted men.[5] Karlsruhe and the rest of II Scouting Group provided the cruiser screen for the task force. On 24 September, Karlsruhe departed Kiel, bound for Libau, where she arrived the following day. On 26 September, she helped carry infantry units to Putziger Wiek, where the men were loaded onto the capital ships of the invasion fleet. Karlsruhe thereafter returned to Libau on 2 October, where she embarked two officers and seventy-eight enlisted men from the Saxon Radfahr-Bataillonen (Bicycle Battalion). The ship then left Libau on 11 October as the leader of the 2nd Transport Group.[6][7]

The operation began on the morning of 12 October, when Moltke and the III Squadron ships engaged Russian positions in Tagga Bay while the IV Squadron shelled Russian gun batteries on the Sworbe Peninsula on Ösel.[8] The men aboard Karlsruhe went ashore in Tagga Bay that morning; she left the area in company with ten transport ships on 17 October and escorted them back to Libau.[7] Over the course of the next two days, Karlsruhe and the rest of II Scouting Group covered minesweepers operating off the island of Dagö, but due to an insufficient number of minesweepers and bad weather, the operation was postponed.[9] By 20 October, the islands were under German control and the Russian naval forces had either been destroyed or forced to withdraw. The Admiralstab then ordered the naval component to return to the North Sea.[10] Karlsruhe returned to Kiel before proceeding to the North Sea on 27 October, where she resumed coastal defense duties. From 16 November to 6 December, she underwent periodic maintenance.[7]

In early April 1918, Karlsruhe supported the laying of a defensive minefield in the North Sea that was laid in preparation for a major fleet operation later that month. She then took part in the abortive fleet operation on 23–24 April to attack British convoys to Norway. I Scouting Group and II Scouting Group, along with the Second Torpedo-Boat Flotilla were to attack a heavily guarded British convoy to Norway, with the rest of the High Seas Fleet steaming in support. During the operation, Karlsruhe and Graudenz were the leading vessels in the German formation. While steaming off the Utsira Lighthouse in southern Norway, Moltke had a serious accident with her machinery, which led Scheer to break off the operation and return to port by 25 April.[7][11] From 10 to 13 May, Karlsruhe and the rest of II Scouting Group escorted the minelayer Senta while the latter vessel laid a defensive minefield to block British submarines form operating in the German Bight. Later that month, she escorted the new dreadnought battleship Baden. II Scouting Group thereafter conducted additional training in the Baltic from 11 to 12 July. Karlsruhe's commander served as the commander of the group while the group commander, Kapitän zur See (KzS—Captain at Sea) Magnus von Levetzow, was away for the meetings that led to the formation of the Seekriegsleitung (SKL—Maritime Warfare Command). Levetzow returned on 5 August, Karlsruhe having gone into the shipyard for maintenance on 1 August.[12]

Karlsruhe in Scapa Flow

Karlsruhe took part in evacuation efforts on the coast of Flanders on 14 August in the aftermath of the Battle of Amiens. She loaded seventy mines, with the intention of laying a minefield in company with the cruisers Brummer and Nürnberg, but the operation was cancelled when it became clear that Nürnberg had to be drydocked for repairs. Karlsruhe took part in training operations in the Baltic from 16 to 23 October, after which she resumed guard duties in the German Bight.[7] Later that month, Karlsruhe and the rest of the II Scouting Group were to lead a final attack on the British navy. Karlsruhe, Nürnberg, and Graudenz were to bombard targets in Flanders while Pillau, Cöln, Dresden, and Königsberg were to attack merchant shipping in the Thames estuary, to draw out the British Grand Fleet.[13] Admirals Reinhard Scheer and Franz von Hipper intended to inflict as much damage as possible on the British navy, to secure a better bargaining position for Germany, whatever the cost to the fleet. On the morning of 29 October 1918, the order was given to sail from Wilhelmshaven the following day. Starting on the night of 29 October, sailors on Thüringen and then on several other battleships mutinied. The unrest ultimately forced Hipper and Scheer to cancel the operation.[14]

Following the capitulation of Germany in November 1918, most of the High Seas Fleet's ships, under the command of Rear Admiral Ludwig von Reuter, were interned in the British naval base in Scapa Flow.[15] Karlsruhe was among the ships interned, and the II Scouting Group commander, KzS Victor Harder, came aboard Karlsruhe for the voyage to internment since his normal flagship, Königsberg, was not included on the list of ships to be interned.[1] The fleet remained in captivity during the negotiations that ultimately produced the Versailles Treaty. Von Reuter believed that the British intended to seize the German ships on 21 June 1919, which was the deadline for Germany to have signed the peace treaty. Unaware that the deadline had been extended to the 23rd, Reuter ordered the ships to be sunk at the next opportunity. On the morning of 21 June, the British fleet left Scapa Flow to conduct training maneuvers, and at 11:20 Reuter transmitted the order to his ships;[16] Karlsruhe sank at 15:50, one of the last ships of the fleet to sink. She was never raised for scrapping, as she had sunk in a greater depth than many of the other ships. The rights to her wreck were sold in 1962, and some non-ferrous metals were removed from the wreck.[1][7]

In 2017, marine archaeologists from the Orkney Research Center for Archaeology conducted extensive surveys of Karlsruhe and nine other wrecks in the area, including six other German and three British warships. The archaeologists mapped the wrecks with sonar and examined them with remotely operated underwater vehicles as part of an effort to determine how the wrecks are deteriorating.[17] The wreck at some point came into the ownership of the firm Scapa Flow Salvage, which sold the rights to the vessel to Tommy Clark, a diving contractor, in 1981. Clark listed the wreck for sale on eBay with a "buy-it-now" price of £60,000, with the auction lasting until 28 June 2019.[18] The wreck of Karlsruhe ultimately sold for £8,500 to a private buyer, while the three dreadnoughts Clark had also placed for sale were purchased by a company from the Middle East for £25,500 apiece.[19] Her wreck lies at 25 m (82 ft) and remains a popular site for recreational scuba divers.[20]