HMS Wolsey number became G40 in June 1918; it was changed to D98 during the interwar period. Upon completion, "Wolsey" was assigned to the Grand Fleet, based at Scapa Flow in the Orkney Islands, in which she served for the rest of World War I. After the conclusion of World War I, "Wolsey" served in the Atlantic Fleet. In the late 1920s, she operated on the China Station. After the British river steamer SS "Kutwo" collided with and sank a Chinese troop-carrying launch on the Yangtze River and Chinese authorities threatened to seize her at Nanking in early March 1927, "Wolsey" arrived
Naval warfare of World War I came under Bulgarian control in 1916 as "Podvodnik No. 18". Russian mines sank one Bulgarian torpedo boat and damaged one more during the war. In the Baltic Sea, Germany and Russia were the main combatants, with a number of British submarines sailing through the Kattegat to assist the Russians. With the German fleet larger and more modern (many High Seas Fleet ships could easily be deployed to the Baltic when the North Sea was quiet), the Russians played a mainly defensive role, at most attacking convoys between Germany and Sweden. A major coup for the Allied forces occurred on August