Although their gross tonnages were different AZUMA and ARIMA MARUs were almost identical sisters. In 1938, passenger-cargo ship AZUMA MARU was requisitioned by the IJA from the Nippon Yusen Kaisha (NYK) Line and returned to her owners later that year. In 1941, AZUMA MARU was requisitioned by the IJN as a general purpose vessel. Later, she served as a troop transport. In 1943, she was converted to an oiler. Later that year, AZUMA MARU was torpedoed and sunk by an American submarine off Palau.

In December 1942, passenger-cargo ship ARIMA MARU was requisitioned by the IJN from the NYK Line and shortly thereafter converted to an oiler. ARIMA MARU was torpedoed and sunk by an American submarine off Palau in 1943.

Earlier, sister ships, ASAKA, AKAGI and AWATA MARUs had been requisitioned from NYK and converted to armed merchant cruisers. ASAKA MARU was sunk by USN aircraft in 1944. AWATA MARU was sunk by an American submarine in 1943 and AKAGI MARU was sunk at Truk in 1944.