Imperial Japanese Navy

The Imperial Japanese Navy (IJN), officially Navy of Empire of Greater Japan, also known as the Japanese Navy was the Navy of Empire of Japan from 1869. It was the third largest navy in the world by 1920 behind United States Navy and British Royal Navy, and perhaps the most modern at the brink of World War II. It was supported by Imperial Japanese Navy Air Service for aircraft and airstrike operation from the fleet.

The origins of the Imperial Japanese Navy trace back to early interactions with nations on the Asian continent, beginning in the early medieval period and reaching a peak of activity during the 16th and 17th centuries at a time of cultural exchange with European powers during the Age of Discovery. After two centuries of stagnation during the country's ensuing seclusion policy under the shoguns of the Edo period, Japan's Navy was comparatively backward when the country was forced open to trade by American intervention in 1854. This eventually led to the Meiji Restoration, a period of frantic modernization and industrialization accompanied by the re-ascendance of the emperor.

The IJN's role in the invasion and conquest of Hawaii in December, 1941 was critical. It was only with assent of the IJN that the invasion was made possible.