Japan: Advertising poster for the Japan Mail Steamship Company (1940). 'Three new sister ships' were...

The Nitta Maru was a Japanese ocean liner owned by Nippon Yusen Kaisha. The ship was built in 1938-1940 by Mitsubishi Shipbuilding & Engineering Co. at Nagasaki, Japan. The vessel's pre-war design anticipated passenger service; but when work was completed, the onset of war had created somewhat different priorities. The vessel was created as a sister ship of the Yawata Maru, and the Kasuga Maru. Each in succession was re-fitted as a troopship; and each was later converted to an aircraft carrier. In 1941, Kasuga Maru was re-commissioned as the Japanese aircraft carrier Taiyo and in 1942, the Yawata Maru was recommissioned as the Japanese aircraft carrier Unyo. In November 1942, the Nitta Maru was recommissioned as the Japanese aircraft carrier Cho«yo.