[6] Japan undertook major naval building efforts in the 16th century, during the Warring States period when feudal rulers vying for supremacy built vast coastal navies of several hundred ships.

[citation needed] The Morrison Incident in 1837 and news of China's defeat during the Opium War led the shogunate to repeal the law to execute foreigners, and instead to adopt the Order for the Provision of Firewood and Water.

[citation needed] As soon as Japan opened up to foreign influences, the Tokugawa shogunate recognized the vulnerability of the country from the sea and initiated an active policy of assimilation and adoption of Western naval technologies.

[citation needed] On 26 March 1868 the first naval review in Japan took place in Osaka Bay, with six ships from the private domain navies of Saga, Chōshū, Satsuma, Kurume, Kumamoto and Hiroshima participating.

[citation needed] The incident involving Enomoto Takeaki's refusal to surrender and his escape to Hokkaidō with a large part of the former Tokugawa Navy's best warships embarrassed the Meiji government politically.

[citation needed] After the Imo Incident in July 1882, Iwakura Tomomi submitted a document to the daijō-kan titled "Opinions Regarding Naval Expansion" asserting that a strong navy was essential to maintaining the security of Japan.

[33] During the 1880s, France took the lead in influence, due to its "Jeune École" ("young school") doctrine, favoring small, fast warships, especially cruisers and torpedo boats, against bigger units.

[34][38] Japan turned again to Britain, with the order of a revolutionary torpedo boat, Kotaka, which was considered the first effective design of a destroyer,[33] in 1887 and with the purchase of Yoshino, built at the Armstrong works in Elswick, Newcastle upon Tyne, the fastest cruiser in the world at the time of her launch in 1892.

The Japanese naval leadership was generally cautious and even apprehensive at the prospect of hostilities with China,[40] as the navy had not yet received several modern warships that had been ordered in February 1893, particularly the battleships Fuji and Yashima and the cruiser Akashi.

An early victory over the Beiyang fleet would allow Japan to transport troops and material to the Korean Peninsula; additionally, the Japanese judged that a protracted war with China would increase the risk of intervention by the European powers with interests in East Asia.

Lastly, if the Combined Fleet was defeated and consequently lost command of the sea, the bulk of the army would remain in Japan and prepare to repel a Chinese invasion, while the Fifth Division in Korea would be ordered to dig in and fight a rearguard action.

[43] A Japanese squadron intercepted and defeated a Chinese naval force near Korean island of Pungdo, damaging a cruiser, sinking a loaded transport, capturing one gunboat and destroying another.

The next step of the Imperial Japanese Navy's expansion would thus involve a combination of heavily armed large warships, with smaller and more innovative offensive units permitting aggressive tactics.

[56] This was used to fund the bulk of the naval expansion, roughly ¥139 million, with public loans and existing government revenue providing the rest of the financing required over the ten years of the program.

Commercial shipbuilding in Japan was exhibited by construction of the twin screw steamer Aki-Maru, built for Nippon Yusen Kaisha by the Mitsubishi Dockyard & Engine Works in Nagasaki.

[66] The period immediately following the Battle of Tsushima also saw the IJN, under the influence of the navalist theoretician Satō Tetsutarō, adopt an explicit policy of preparing for a potential future conflict against the U.S. Navy.

[73] An IJN battle group was also sent to the central Pacific between August and September to pursue the German East Asia squadron, which then moved into the Southern Atlantic, where it encountered British naval forces and was destroyed near the Falkland Islands.

Japan also seized German possessions in northern Micronesia, which remained under Japanese control as colonies until the end of World War II, under the League of Nations' South Seas Mandate.

This force consisted of one protected cruiser, Akashi, as flotilla leader and eight of the Navy's newest Kaba-class destroyers (Ume, Kusunoki, Kaede, Katsura, Kashiwa, Matsu, Sugi, and Sakaki), under Admiral Satō Kōzō.

Over the course of the Sempill mission's stay, Japanese technicians became familiar with the newest aerial weapons and equipment, including torpedoes, bombs, machine guns, cameras, and communications gear.

By the time the mission's last members had returned to Britain, the Japanese had acquired a reasonable grasp of the latest aviation technology and taken the first steps toward building an effective naval air force.

Throughout the 1930s, Japanese politics became increasingly dominated by militaristic leaders who prioritized territorial expansion, and who eventually came to view the United States as Japan's main obstacle to achieving this goal.

Kantai kessen evolved from the writings of geopolitical theorist Alfred T. Mahan, which hypothesized that wars would be decided by large, decisive engagements at sea between opposing surface fleets.

A consistent weakness of Japanese warship development was the tendency to incorporate excessive firepower and engine output relative to ship size, which was a side-effect of the Washington Treaty limitations on overall tonnage.

Although the 1937–41 air offensives failed in their political and psychological aims, they did reduce the flow of strategic materiel to China, and for a time improved the Japan's military situation in the central and southern parts of the country.

[112][107][113] Crucially, relying heavily on the use of aggressive tactics which stemmed from Mahanian doctrine and the concept of decisive battle,[114] Japan did not invest significantly in capabilities needed to protect its long shipping lines against enemy submarines.

[124] The catastrophic defeat at the Philippine Sea in June 1944 was a disaster for Japanese naval air power, with the bulk of the IJN's highly-trained and, at this point in the war, largely irreplaceable carrier pilots shot down.

[127] During the last phase of the war, the Imperial Japanese Navy resorted to a series of desperate measures, including a utilization of Special Attack Units, popularly called kamikazes.

[128] By May 1945, much of the Imperial Japanese Navy had been sunk, and surviving IJN warships had taken refuge in harbors on the Home Islands, due to both a lack of fuel and an inability to contend with overwhelming American naval airpower.

In the new constitution of Japan, drawn up in 1947, Article 9 specifies that "the Japanese people forever renounce war as a sovereign right of the nation and the threat or use of force as a means of settling international disputes.