Submarines of the Imperial Japanese Navy
Imperial Japanese Navy submarines originated with the purchase of five Holland type submarines from the United States in 1904. Japanese submarine forces progressively built up strength and expertise, becoming by the beginning of World War II one of the world's most varied and powerful submarine fleets.
Submarine chaser
The Imperial Japanese Navy had around 250 submarine chasers in World War II, principally about 200 of the No.1-class auxiliary submarine chasers. Some of these survived to serve in the Japan Maritime Self Defense Force (JMSDF) after the war.