was a warship of the Imperial Japanese Navy during World Wars I and II. She was the first battlecruiser of the , among the most heavily armed ships in any navy when built. Her designer was British naval engineer George Thurston, and she was laid down in 1911 at Barrow-in-Furness in Britain by Vickers Shipbuilding Company. Kongō was the last Japanese capital ship constructed outside Japan. She was commissioned formally in 1913 and patrolled off the Chinese coast during World War I.

Kongō underwent two major reconstructions. Beginning in 1929, the Imperial Japanese Navy (IJN) rebuilt her as a battleship, strengthening her armor and improving her speed and power capabilities. In 1935, her superstructure was completely rebuilt, her speed was increased, and she was equipped with launch catapults for floatplanes. Now fast enough to accompany Japan's growing carrier fleet, Kongō was reclassified as a fast battleship. During the Second Sino-Japanese War, Kongō operated off the coast of mainland China before being redeployed to the Third Battleship Division in 1941. In 1942, she sailed as part of the Southern Force in preparation for the Battle of Singapore.

Kongō fought in many major naval actions of the Pacific War during World War II. She covered the Japanese Army's amphibious landings in British Malaya (part of present-day Malaysia) and the Dutch East Indies (now Indonesia) in 1942, before engaging American forces at the Battle of Midway and during the Guadalcanal campaign. Throughout 1943, Kongō primarily remained at Truk Lagoon in the Caroline Islands, Kure Naval Base (near Hiroshima), Sasebo Naval Base (near Nagasaki), and Lingga Roads, and deployed several times in response to American aircraft carrier air raids on Japanese island bases scattered across the Pacific. Kongō participated in the Battle of the Philippine Sea (19-20 June) and the Battle of Leyte Gulf in 1944 (22–23 October), sinking the destroyer escort and helping to cripple the destroyer in the latter engagement. Kongō was torpedoed and sunk by the submarine while transiting the Formosa Strait on 21 November 1944. She was the only Japanese battleship sunk by a submarine in the Second World War.

Design and construction

Kongō was the first of the IJN's Kongō-class battlecruisers, which were almost as large, costly, and well-armed as battleships, but traded off armored protection for higher speeds. These were designed by British naval engineer George Thurston and were ordered in 1910 in the Japanese Emergency Naval Expansion Bill after the commissioning of in 1908. These four battlecruisers of the Kongō class were designed to match the naval capabilities of the battlecruisers of the other major naval powers at the time, and they have been called the battlecruiser versions of the British (formerly Turkish) battleship .Friedman 1985, p. 234 Their heavy armament of 14-inch naval guns and their armor protection (which took up about 23.3% of their roughly 30,000-ton displacements in 1913) were greatly superior to those of any other Japanese capital ship afloat at the time.

The keel of Kongō was laid down at Barrow-in-Furness by Vickers Shipbuilding and Engineering on 17 January 1911. Under Japan's contract with Vickers, the first vessel of the class was constructed in the United Kingdom, with the remainder built in Japan. Kongō was launched on 18 May 1912 and then transferred to the dockyards of Portsmouth, England, where her fitting-out began in mid-1912. All parts used in her construction were manufactured in the U.K. Kongō was completed on 16 April 1913.

Siemens-Vickers Scandal

In January 1914, a telegram leaked from German industrial conglomerate Siemens' Tokyo office to Reuters along with further reporting by The New York Times and The Asahi Shimbun led to an investigation by Japanese authorities, which revealed a pattern of bribery and kickbacks by German and English armaments corporations. Siemens had been paying senior Japanese officials a secret 15% kickback, until British company Vickers had outbid them by offering 25%. Vickers had paid 210,000 yen to Admiral Fuji of the IJN procurement in 1911 and 1912, and 40,000 yen to Vice Admiral Matsumoto Kazu, related to obtaining the contract for building Kongō. Kazu was court-martialed in May 1914, fined 400,000 yen, and sentenced to 3 years in prison. As a result of the Siemens-Vickers scandal revolving around the contracts for building Kongō, the government of Prime Minister Yamamoto Gonnohyōe resigned March 23, 1914. Senior executives of Mitsui corporation, Japanese partners of Vickers, also resigned.

Armament

Originally, Kongōs main battery was designed to consist of ten 12-inch (305 mm) main guns. Her builders, Vickers, convinced the Japanese to go with a larger weapon, though, after Kongō was laid down. Because of this, Kongōs main armament as built consisted of eight Vickers 14 inch (356 mm)/45 naval gun heavy-caliber main naval guns in four twin turrets (two forward and two aft), making her the most powerfully armed capital ship when she was commissioned. The turrets were noted by the U.S. Office of Naval Intelligence to be "similar to the British 15-inch turrets", with improvements made in flash-tightness. Each of her main guns could fire high explosive or armor-piercing shells at a rate of about two shells per minute. In keeping with the Japanese doctrine of deploying more powerful vessels before their opponents, Kongō and her sister ships were the first vessels in the world equipped with guns.Jackson (2000), p. 48 Her main guns carried ammunition for 90 shots, and they had an approximate barrel lifetime of 250 to 280 shots. In 1941, separate dyes were introduced for the armor-piercing shells of the four Kongō-class battleships to assist with targeting, with Kongōs armor-piercing shells using red dye.

The secondary battery of Kongō originally consisted of sixteen 50-calibre guns in single casemates located amidships ("50-calibre" means that the lengths of the guns were 50 times their bore, or 300 inches), sixteen guns, and eight submerged torpedo tubes. Her 6-inch naval guns could fire five to six rounds per minute, with a barrel lifetime around 500 rounds. The 6-inch/50-calibre gun was capable of firing both antiaircraft and antiship shells, though the positioning of these guns on Kongō made antiaircraft firing mostly impractical. During her second reconstruction, the older three-inch guns were removed and then replaced with eight 5-inch (127 mm) 40-calibre, dual-purpose guns. These guns could fire from eight to 14 rounds per minute, with a barrel lifetime between 800 and 1,500 rounds. Of Kongōs guns, the 5-inch guns had the widest variety of shell types: antiaircraft, antiship, and illumination shells. Kongō was also armed with many antiaircraft machine guns. By October 1944, Kongōs secondary armament was reconfigured to eight guns, eight guns, and 122 Type 96 antiaircraft rapid-fire cannons.Stille (2008), p. 16

Armor Being a battlecruiser, Kongōs armor was fairly thin. She was equipped with a 6- to 8-inch (152–203 mm) main belt. Kongō deck armor consisted of armor plating ranging from 1-inch (25 mm), 1.5-inches (38 mm), to 2.75-inches (7 cm), depending on the area. She was equipped with 9-inch (229 mm) barbette armor protecting the ammunition to her main guns, as well as turret armor consisting of 10-inch (254 mm) turret faces, and 9-inch (229 mm) plating over the sides and rear.

Service history 1913–1929: Battlecruiser

On 16 August 1913, Kongō was completed and commissioned into the IJN; 12 days later, she departed from Portsmouth headed for Japan.Stille (2008), p. 14 She was docked at Singapore from 20 to 27 October, before arriving at Yokosuka Naval Arsenal on 5 November, where she was placed in first reserve. In January 1914, she docked at Kure Naval Base for armament checks. On 3 August 1914, the German Empire declared war on France and then invaded via Belgium, sparking the beginning of World War I in the West. Twelve days later, Japan issued a warning to Kaiser Wilhelm II of the German Empire, ordering him to withdraw the German troops from their base at Qingdao, China. When the German Empire did not respond, Japan declared war on Germany on 23 August, occupying the former German possessions in the Caroline Islands, Palau Islands, Marshall Islands, and Marianas Islands. Kongō was quickly deployed towards the Central Pacific to patrol the sea lines of communication of the German Empire. Kongō returned to the port of Yokosuka, Japan, on 12 September, and one month later, she was assigned to the First Battleship Division. In October, Kongō and her new sister ship sortied off the Chinese coast in support of Japanese army units during the Siege of Tsingtao. Then, Kongō returned to Sasebo Naval Base for upgrades to her searchlights. On 3 October 1915, Kongō and Hiei participated in the sinking of the old as a practice target. She was a Russian predreadnought that had been captured in 1905 during the Russo-Japanese War that had next served as an IJN warship.McLaughlin (2003), pp. 44–45 With the defeat of the German East Asia Squadron by the Royal Navy at the Battle of the Falkland Islands in December 1914, the need for IJN operations in the Pacific Ocean was greatly reduced. Kongō spent the rest of World War I either based at Sasebo or on patrol off the coast of China. In December 1918, following the end of the hostilities of World War I, Kongō was placed in "second reserve". In April 1919, she was fitted with a new seawater flooding system for her ammunition magazines.

With the conclusion of World War I and the signing of the Washington Naval Treaty on 6 February 1922, the size of the IJN was significantly limited, with a ratio of 5:5:3 required between the capital ships of the United Kingdom, the United States, and the Japanese Empire, since the last was responsible for only one ocean, rather than the two of the other countries, and fewer warships for France and Italy.Jackson (2000), p. 67. This treaty also banned the signatories from building any new capital ships until 1931, with no capital ship permitted to exceed in displacement.Jackson (2000), p. 68. Provided that new additions did not exceed 3,000 tons of displacement, the existing capital ships were allowed to be upgraded with improved antitorpedo bulges and armored main decks. By the time that the Washington Naval Treaty had been fully implemented in Japan, only three classes of World War I-type capital ships remained active - the s, the Kongō-class battlecruisers, and the s.Jackson (2000), p. 69

In April 1923, Kongō gave transportation to Crown Prince Hirohito during his official visit to the Japanese possession of Taiwan. On 14 June 1924, she collided with Submarine No. 62 during maneuvers.Airship Investigation: Report of Col. Henry Breckenridge, Washington, D.C.: Government Printing Office, 1933, p. 56. In November 1924, Kongō docked at Yokosuka, where modifications were made to her main armament, increasing the elevation of her main guns and improving her fire-control systems. In 1927, Kongō underwent major modifications to her superstructure, rebuilding it into the pagoda mast style to accommodate the growing number of fire-control systems for her main guns.Stille (2008), p. 15 In May 1928, her steering equipment was upgraded, before she was placed in reserve in preparation for major modifications and reconstruction in 1929–31.

1929–1935: Reconstruction into battleship