Between the 1890s and 1940s, the Imperial Japanese Navy (IJN) built a series of battleships as it expanded its fleet. Previously, the Empire of Japan had acquired a few ironclad warships from foreign builders, although it had adopted the naval doctrine which emphasized cheap torpedo boats and commerce raiding to offset expensive, heavily armored ships. To counter the Beiyang Fleet of Imperial China in the early 1890s, however, Japan ordered two s from Great Britain as Japan lacked the technology and capability to construct its own vessels. Combat experience in the First Sino-Japanese War of 1894–1895 convinced the IJN that its doctrine was untenable, leading to a ten-year naval construction program that called for a total of six battleships and six armored cruisers (the Six-Six Fleet). The two ships of the and the battleships and were also purchased from Great Britain. Aware that they could not outbuild the Americans or British, the IJN decided that their ships would always be qualitatively superior to offset their quantitative inferiority.
To counter reinforcement of the Russian Empire's Pacific Squadron as tensions rose between the Russians and the Japanese over control of Korea and Manchuria in the early 1900s, Japan ordered the two battleships of the in 1903, the last battleships ordered from abroad. To preempt further reinforcements before their own ships were completed, they began the Russo-Japanese War in 1904 with a surprise attack on the Russian base at Port Arthur. Shortly after the war began, the IJN ordered the two ships of the , the first battleships to be built in Japan. The Imperial Japanese Army captured Port Arthur, along with the surviving ships of the Pacific Squadron by the end of the year. The Russians had dispatched the bulk of their Baltic Fleet to relieve Port Arthur, which reached the Korea Strait in May 1905 and was virtually annihilated by the IJN in the Battle of Tsushima. During the war, Japan captured a total of five Russian pre-dreadnought battleships. They were repaired and commissioned into the Japanese fleet, and two were later sold back to Russia during World War I, as Japan and Russia were by then allies. The magnitude of the victory at Tsushima caused the leadership of the IJN to believe that a surface engagement between the main fleets was the only decisive battle in modern warfare and would be decided by battleships armed with the largest guns.
After the war, the Japanese Empire immediately turned its focus to the two remaining rivals for imperial dominance in the Pacific Ocean, Britain and the United States, believing that conflict would inevitably arise between Japan and at least one of its two main rivals. Accordingly, the 1907 Imperial Defense Policy called for the construction of a battle fleet of eight modern battleships and eight battlecruisers. This was the genesis of the Eight-Eight Fleet Program, the development of a cohesive battle line of sixteen capital ships. The launch of in 1906 and the battlecruiser the following year by the Royal Navy raised the stakes and complicated Japan's plans as they rendered all existing battleships and armored cruisers obsolete, forcing Japan to restart the Eight-Eight plan with dreadnought battleships and battlecruisers. This began with the in 1907, followed by the and es in the 1910s. Japan ordered its seventh and eighth dreadnoughts with the in 1916 and 1917.
In 1919, American president Woodrow Wilson announced the resumption of the 1916 naval construction program and the Japanese ordered eight fast battleships of the and es in response. The prospect of a new massively expensive arms race between the United States, Britain and Japan after the war caused the three powers to agree to the Washington Naval Treaty which limited Japan to a ratio of 3:5:5 in battleship tonnage to the United States and Britain. The treaty forced the IJN to dispose of all of its pre-dreadnoughts and the oldest dreadnoughts; the ships then under construction had to be broken up or sunk as targets. Furthermore, the treaty mandated a building holiday that barred the construction of new battleships for ten years. During this period, opponents of the Washington Naval Treaty and its successors had taken control of the upper echelons of the IJN and rebuilt the s into fast battleships and modernized the existing ships. Coupled with the growth of ultranationalism and dominance of the government by the military, the government decided to withdraw from the treaty regime when it expired in 1936. Planning by the Navy General Staff for the post-treaty era began in 1934 and included five large battleships armed with nine guns; these ships became the . While the Yamatos were under construction in the late 1930s, the IJN began designing a successor class, the Design A-150 armed with guns, but never laid any down as they prepared for war and other ships had higher priority.
Key + Key Armament The number and type of the primary armament Armor The thickness of the belt armor Displacement Ship displacement at normal load Propulsion Number of shafts, type of propulsion system, and designed speed Service The dates work on the ship began and finished and its ultimate fate Laid down The date the keel began to be assembled Commissioned/Captured The date the ship was commissioned or captured
Pre-dreadnoughts
Fuji class
The two ships, and , were the IJN's first battleships, ordered from Britain in response to two new German-built Chinese ironclad warships. The ships were designed as smaller versions of the British , although they were slightly faster and had a better type of armor.
As part of the 1st Fleet the Fujis participated in fighting off Port Arthur on 9–10 March 1904, wherein Fuji sustained light damage and Yashima was undamaged. On 15 May Yashima struck two naval mines and foundered. Fuji participated in the Battle of the Yellow Sea in August and was then slightly damaged during the Battle of Tsushima in May 1905. She was credited with the shot that caused the magazine explosion that destroyed the battleship . In October 1908, Fuji hosted the American ambassador to Japan and some senior officers of the Great White Fleet, and was later reclassified as a coast defense ship in 1910. The ship was disarmed and converted into an accommodation ship in 1922. Fuji was sunk by American aircraft in 1945 and scrapped in 1948.
Ship Armament Armor Displacement Propulsion Service Laid down Commissioned Fate () 2 × twin 2 shafts, 2 triple-expansion steam engines,1 August 189417 August 1897Broken up, 1948 ()6 December 18949 September 1897Sank after striking a mine, 15 May 1904
Shikishima class
The was designed as a more powerful version of the Royal Navy's battleship. The ships were also assigned to the 1st Fleet before the Russo–Japanese War, were present at the Battle of Port Arthur and were slightly damaged during the action. struck one of the mines that the Russians laid in May 1904 and sank following a magazine explosion. Shikishima fought in the Battle of the Yellow Sea, only being damaged by a misfiring 12-inch shell, and then participated in the Battle of Tsushima where she was hit nine times, suffered another misfire from one of her main guns, and, together with the battleship , sank the Russian battleship . Shikishima spent the duration of World War I assigned to the Sasebo Naval District, and was demilitarized after the Washington Naval Treaty was signed in 1922. She was used as a training hulk at Sasebo until she was broken up in 1948.
Ship Armament Armor Displacement Propulsion Service Laid down Commissioned Fate () 2 × twin 12 in guns 2 shafts, 2 triple-expansion steam engines,29 March 189726 January 1900Broken up, January 1948 ()10 January 189818 January 1901Sank 15 May 1904, after striking two mines
Asahi
Asahi was a slightly improved version of the British s. She became the flagship of the IJN's Standing Fleet and was later assigned to the 1st Fleet when the Combined Fleet reformed in 1903. At the start of the Russo–Japanese War, Asahi took part in the Battle of Port Arthur and was not damaged by Russian fire. At the Battle of the Yellow Sea, the ship was moderately damaged, although she hit and damaged and in return. Asahi struck a mine two months later near Port Arthur, but was repaired in time for the Battle of Tsushima. There, she helped disable the battleship and dueled with the battleships Borodino and , taking no damage.
She was a gunnery training ship for most of World War I until being rearmed in 1917 in time to escort troop transports during Japan's intervention in the Russian Civil War. Asahi was converted into a noncombat vessel during the 1920s and was then made a repair ship in 1937. On the night of 25–26 May 1942, Asahi was torpedoed and sunk by the submarine off modern-day Vietnam.
Ship Armament Armor Displacement Propulsion Service Laid down Commissioned Fate () 2 × twin 12 in guns 9 in 2 shafts, 2 triple-expansion steam engines,18 knots 1 August 1897 31 July 1900 Sunk by , 25–26 May 1942
Mikasa
Mikasa was also an improved version of the Formidable-class battleships and only differed in minor respects from Asahi. The ship served as the 1st Fleet flagship throughout the Russo-Japanese War. She participated in the Battle of Port Arthur on the second day of the war and the Battles of the Yellow Sea and Tsushima. During the latter battle, the ship was hit many times, but was only lightly damaged. Days after the end of the war, Mikasas magazine accidentally exploded and sank the ship. She was salvaged and her repairs took over two years to complete. Afterward, the ship served as a coast-defense ship during World War I and supported Japanese forces when they intervened in the Russian Civil War. After the Washington Naval Treaty was ratified in 1922 Mikasa was preserved as a museum ship. She was badly neglected during the post–World War II occupation of Japan and required extensive refurbishing in the late 1950s, but has only partially been restored. Mikasa is the only surviving example of a pre-dreadnought battleship in the world.
Ship Armament Armor Displacement Propulsion Service Laid down Commissioned Fate () 2 × twin 12 in guns 9 in 2 shafts, 2 triple-expansion steam engines,18 knots 24 January 1899 1 March 1902 Preserved as a museum ship
Tango
Tango was laid down as the Russian battleship Poltava (), the second of three pre-dreadnought battleships. The ship was assigned to the Pacific Squadron shortly after her completion and based at Port Arthur from 1901. During the Russo-Japanese War, she participated in the Battle of Port Arthur and was heavily damaged during the Battle of the Yellow Sea. Sunk by Japanese artillery during the subsequent Siege of Port Arthur in December 1904, she was refloated by the IJN after the war and subsequently renamed Tango. During World War I, she bombarded German fortifications during the Siege of Tsingtao. The Japanese government sold Tango back to the Russians in 1916. She was renamed Chesma () as her former name had been given to a new ship. Her crew declared for the Bolsheviks in October 1917, but saw no action in the Russian Civil War owing to her poor condition, and she was ultimately scrapped in 1924.
Ship Armament Armor Displacement Propulsion Service Laid down Captured Fate () 4 × 12 in guns Krupp armor 2 shafts, 2 triple-expansion steam engines, 19 May 1892 2 January 1905 Returned to Russia, 1916, scrapped, 1924
Sagami and Suwo
Sagami and Suwo were originally the Russian battleships () and () respectively. The design of the Peresvet class was inspired by the British second-class battleships of the . The British ships were intended to defeat commerce-raiding armored cruisers like the Russian ships and , and the Peresvet class was designed to support their armored cruisers.