Imperial Japanese Navy

• 1. Origins And Early Naval History

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  In 1576, the daimyō Oda Nobunaga commissioned six iron-covered warships known as Oatakebune. These vessels represented one of the earliest attempts at creating an ironclad fleet in history, predating similar Western developments by nearly three centuries. The ships were constructed during a period of intense feudal warfare when rulers vied for supremacy across Japan. Coastal navies expanded rapidly during the Warring States period, with some domains maintaining fleets of several hundred ships. By 1588, Toyotomi Hideyoshi issued a ban on Wakō piracy, transforming these former raiders into official naval forces used during the Japanese invasion of Korea from 1592 to 1598. Japan built its first large ocean-going warship, the Date Maru, in 1613. This 500-ton galleon transported Hasekura Tsunenaga's embassy to the United States before continuing to Europe. Between 1604 and 1640, the Bakufu commissioned approximately 350 Red seal ships armed with Western technology primarily for Southeast Asian trade.

• 2. Meiji Restoration And Centralization

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  The Meiji Restoration began in 1868, overthrowing the Tokugawa shogunate and establishing imperial rule. From January 1868 to June 1869, the Boshin War involved minimal naval combat despite transporting troops between western and eastern Japan. Only the Battle of Awa on the 28th of January 1868 proved significant among early engagements. On the 26th of March 1868, the first naval review took place in Osaka Bay featuring six ships from private domain navies totaling 2,252 tons. This was far smaller than a single French Navy vessel that also participated. Enomoto Takeaki, admiral of the shōgun's navy, refused surrender and escaped to northern Honshū with eight steam warships and 2,000 men. He established the breakaway Republic of Ezo on the 27th of January 1869. The Imperial side received the French-built ironclad Kotetsu in February 1869, using it decisively during the Naval Battle of Hakodate in May 1869. In 1871, domains were abolished altogether, allowing centralization of all naval forces under the government. By October 1873, Katsu Kaishū became Navy Minister following his recommendation for rapid centralization of all naval forces.

• 3. British Influence And First Expansion

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  An imperial decree in 1870 determined that Britain's Royal Navy should serve as the model for development instead of the Netherlands navy. A thirty-four-man British mission led by Lt. Comdr. Archibald Douglas arrived in Japan in 1873 and remained until 1879. They directed instruction at the Naval Academy at Tsukiji while establishing British traditions throughout matters of seamanship, uniforms, and officer attitudes. From September 1870, English Lieutenant Horse supervised gunnery practice aboard the Ryūjō. In 1871, the ministry sent 16 trainees abroad including Heihachirō Tōgō to Great Britain and two to the United States. Commander L. P. Willan was hired in 1879 to train naval cadets. Ships such as the Naniwa and Takachiho were built in British shipyards as the first warships constructed specifically for the Imperial Japanese Navy. Private companies like Ishikawajima and Kawasaki emerged around this time. After the Imo Incident in July 1882, Iwakura Tomomi submitted a document titled Opinions Regarding Naval Expansion asserting that strong navies maintained security. The government approved a plan in May 1883 adding 32 warships over eight years costing just over ¥26 million.

• 4. Russo-Japanese War And Tsushima

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  The Battle of Tsushima occurred during the Russo-Japanese War when Admiral Togo led the Japanese Grand Fleet into a decisive engagement. Out of 38 Russian ships, 21 were sunk, seven captured, and six disarmed. Casualties included 4,545 Russian servicemen killed and 6,106 taken prisoner. Conversely, Japan lost only 116 men and three torpedo boats. These victories broke Russian naval strength in East Asia while triggering waves of mutinies at Sevastopol, Vladivostok, and Kronstadt peaking in June with the Potemkin uprising. Following the conflict, Japan acquired its first submarines from Electric Boat Company in 1905. Five Holland Type VII submarines shipped in kit form arrived in October 1904 and assembled at Yokosuka Naval Arsenal as hulls No.1 through No.5 becoming operational by end of 1905. By 1920, the Imperial Japanese Navy ranked third largest globally behind Britain and America. The navy employed wireless telegraphy in combat for the first time at the 1905 Battle of Tsushima following Marconi's 1897 invention.

• 5. Interwar Doctrine And Treaty Limitations

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  The Washington Naval Treaty of 1922 established ratios between five signatory powers allocating 525,000 tons to United States and Britain each, 315,000 to Japan, and 175,000 to France and Italy. Maximum displacement limits reached 35,000 tons per ship prohibiting guns larger than 16 inches. Aircraft carrier construction followed the same 5:5:3 ratio giving Japan 81,000 tons. Despite outrage among naval armament proponents, unfavorable tonnage limitations were preferable to unrestricted arms races with industrially dominant United States. In 1921, Japan launched Hōshō, the world's first purpose-built aircraft carrier completed that year. Between 1921 and 1928, the navy developed innovative designs including enclosed dual turrets capable of anti-aircraft fire on the Fubuki class destroyers. These vessels featured torpedo tubes enclosed in splinter-proof turrets. The Type 93 oxygen-fueled torpedo became generally recognized as the best weapon of World War Two. Circle plans initiated after London Treaty of 1930 included four major programs approved in 1931, 1934, 1937, and 1939.

• 6. World War II Strategic Failures

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  Japanese planners subscribed to a doctrine called Kantai Kessen or decisive battle requiring comprehensive destruction of enemy naval strength in single large-scale fleet actions. This strategy evolved from writings by Alfred T. Mahan hypothesizing wars decided by surface fleets. Japanese leadership pursued technical superiority through fewer but faster more powerful ships while neglecting antisubmarine warfare capabilities. Japan under-invested significantly in escort ships and escort carriers needed to protect long shipping lines against enemy submarines. Specialized training and organization supporting these areas remained inadequate throughout the conflict. By 1945, the Imperial Japanese Navy had been largely destroyed following surrender ending its existence between 1868 and 1945. The United States Navy emerged victorious having broken diplomatic codes reading signals from government negotiators during Washington Naval Conference negotiations. American Black Chamber successfully decoded Japanese communications allowing enforcement of 60% ratio insisting on parity between navies despite Japanese demands for 70% ratio at conference.