Background
* In 1917, World War I was stagnant. The lengthy war led to an increase in shipping and a shortage of merchant ships. * The IJN utilized steamship companies to perform coal transportation duties. However, this expedient was very costly. The IJN decided to build new colliers under the Eight-four fleet plan. * Their design was ordinary, because the IJN did not impose any special requirements on them.Service
* In the 1920s, they engaged in coal transportation duties. * In February 1932, the ''Muroto'' was remodeled, becoming an auxiliary hospital ship. She was refitted as a supply ship in 1941. * In World War II, the value of coal as fuel fell. The ships engaged in transporting goods and troops.Ships in class
Footnotes
Bibliography
*Monthly Ships of the World, ''Special issue Vol. 47, "Auxiliary Vessels of the Imperial Japanese Navy"'', , (Japan), March 1997 *The Maru Special, ''Japanese Naval Vessels No. 34, "Japanese Auxiliary vessels"'', (Japan), December 1979 *Series 100 year histories from