She was launched and commissioned in March 1915 as SM UB-14 in the German Imperial Navy under the command of Oberleutnant zur See Heino von Heimburg.

[6][Note 2] UB-14 was part of the initial allotment of seven submarines—numbered UB-9 to UB-15—ordered on 15 October from AG Weser of Bremen, just shy of two months after planning for the class began.

[10][Note 3] Those same sources are silent on UB-14's whereabouts at the time, but information on UB-14' later shipment and arrival in the Mediterranean suggest that her initial launch and commissioning may have occurred in Germany.

[14] Von Heimburg and his German crew, with one Austrian officer aboard, gained valuable experience in UB-15/U-11, sinking the Medusa on that U-boat's first patrol.

As a consequence, German submarines operating in the Adriatic and the Mediterranean were all assigned Austrian numbers and flew the flag of Austria-Hungary when making attacks on Italian vessels; UB-14 was assigned the designation of U-26 and entered onto the rolls of the Austro-Hungarian Navy, despite the fact that she remained completely under German control.

[16][18] When the Italian ships retired in the early morning hours of the 7th, UB-14 was about 20 nautical miles (37 km; 23 mi) off Venice.

[21] Since her intermediate refueling stop at Bodrum was beyond her limited range, UB-14 departed Pola under tow from an Austrian destroyer on 15 July 1915.

A repair crew from Constantinople was dispatched—having to travel by train and camel just to reach UB-14—and the ship was ready to resume her journey on 13 August.

[22] Von Heimburg launched one of his two torpedoes from about a mile (2 km) away and hit Royal Edward in the stern;[23] the ship sank stern-first in six minutes, with a large loss of life.

[23][Note 6] Royal Edward, at 11,117 gross register tons (GRT), was also among the largest ships hit by U-boats during the war.

[19] While evading the rescue ships, which included two French destroyers, UB-14's compass broke down again, forcing a return to Bodrum on the morning of the 15th.

[24] During the journey north, UB-14 came upon another fully loaded troopship near the island of Efstratis, about 30 nautical miles (56 km; 35 mi) from Lemnos.

At 09:51 on 2 September,[25] von Heimburg launched a single torpedo at the British troopship Southland, which was carrying mostly Australian troops headed for Gallipoli.

[28] A group of about 40 volunteers stayed on board Southland to help the crew, and with some towing assistance from Ben-my-Chree, were able to beach the ship on Lemnos.

Von Heimburg, Prince Heinrich, and UB-14's cook, a man by the name of Herzig, set out in a rowboat to observe the Turkish attempts to destroy E7.

After several mines that formed part of the net had been detonated to no avail,[Note 8] von Heimburg and his group rowed out and repeatedly dropped a plumb line until it contacted metal.

[32] After the hand-dropped mine detonated too close for the British submarine's captain's comfort, he ordered his boat surfaced, abandoned, and scuttled.

Between shellfire from the Turkish shore batteries and E7's scuttling charges, von Heimburg and company narrowly escaped harm.

[33] During this patrol, von Heimburg torpedoed the 474 GRT Russian steamer Katja about 15 nautical miles (28 km; 17 mi) northwest of Sevastopol on the 7th,[35] and Apscheron, a Belgian steamer expropriated by the Imperial Russian Navy, 24 nautical miles (44 km; 28 mi) south of Cape Chersonesos on the 8th.

While UB-14 had been in port on 30 November, Turkish forces had captured the Turquoise before the submarine or any of the confidential papers on board could be destroyed.

[46] After Romania joined the war on the side of the Triple Entente in August and was quickly overrun by the Central Powers, the Russian efforts in the Black Sea in the second half of 1916 were focused in the west.

[citation needed] On 28 May 1917, Oberleutnant zur See Ernst Ulrich replaced Schwarz,[49] and, soon after, UB-14 sailed on the first German patrol of the year in the Black Sea.

[31] Other than to note that Oberleutnant zur See Bodo Elleke succeeded Ulrich in March 1918,[52] there is no mention in sources of UB-14's activities between June 1917 and November 1918.