Tsushima Maru was carrying a large number of Japanese civilians evacuating from Okinawa to Kagoshima in compliance with government orders to prepare for an invasion of the Ryukyu Islands.

On August 22, 1944, at between 10:00 p.m. and 10:30 p.m. local time, USS Bowfin attacked the convoy in which Tsushima Maru was sailing and sank her, close to the island of Akusekijima.

[5][6] Tsushima Maru Commemoration Association Survey Data (As of August 27, 2005), reported a total of 1,661 civilian evacuees, including 834 schoolchildren (of whom 775 were killed and approximately 59 survived the sinking).

[7] Shortly after the sinking a "gag order" was enforced by the Japanese government and families and survivors rarely spoke about the incident.

The sinking has been the subject of many articles and books published in Japan, as well as a good number of documentary broadcasts and even an animated feature film.