Imperial Japanese Navy - World War I

World War I

Japan entered World War I on the side of the Allies, against Imperial Germany and Austria-Hungary, as a consequence of the 1902 Anglo-Japanese Alliance.

In the Battle of Tsingtao, the Japanese Navy seized the German naval base of Tsingtao. During the battle, beginning on 5 September 1914, Wakamiya conducted the world's first successful sea-launched air strikes. from Kiaochow Bay. Four Maurice Farman seaplanes bombarded German land targets (communication centers and command centers) and damaged a German minelayer in the Tsingtao peninsula from September to 6 November 1914 when the Germans surrendered.

Concurrently, a battle group was sent to the central Pacific in August and September to pursue the German East Asiatic squadron, which then moved into the Southern Atlantic, where it encountered British naval forces and was destroyed at the Battle of the Falkland Islands. Japan seized former German possessions in Micronesia (the Mariana Islands, excluding Guam); the Caroline Islands; and the Marshall Islands), which remained Japanese colonies until the end of World War II, under the League of Nations' South Pacific Mandate.

Hard pressed in Europe, where she had only a narrow margin of superiority against Germany, Britain had requested, but was denied, the loan of Japan's four newest Kongō-class battlecruisers (Kongō, Hiei, Haruna, and Kirishima), the first ships in the world to be equipped with 356 mm (14 in) guns, and the most formidable battlecruisers in the world at the time.

Following a further request to contribute to the conflict, and the advent of unrestricted submarine warfare by Germany, the Imperial Navy in March 1917 sent a special force of destroyers to the Mediterranean. This force, consisting of one armoured cruiser, Akashi, as flotilla leader, and eight of the Navy's newest destroyers (Ume, Kusunoki, Kaede, Katsura, Kashiwa, Matsu, Sugi, and Sakaki), under Admiral Satō Kōzō, was based in Malta and efficiently protected allied shipping between Marseille, Taranto, and ports in Egypt until the end of the War. In June, Akashi was replaced by Izumo, and four more destroyers were added (Kashi, Hinoki, Momo, and Yanagi). They were later joined by the cruiser Nisshin. By the end of the war, the Japanese had escorted 788 allied transports. One destroyer, Sakaki, was torpedoed by an Austrian submarine with the loss of 59 officers and men.

In 1918, ships such as Azuma were assigned to convoy escort in the Indian Ocean between Singapore and the Suez Canal as part of Japan’s contribution to the war effort under the Anglo-Japanese alliance.

After the conflict, the Japanese Navy received seven German submarines as spoils of war, which were brought to Japan and analysed, contributing greatly to the development of the Japanese submarine industry.