 Under the elderly General Iwane Matsui, Nakajima was named Operational Commander in the Battle of Nanjing in late-1937 and was thus the senior officer (aside from the nominal commander in chief Prince Asaka) at the time of the Nanjing massacre.His wartime diary, published in 1985, has proved to be an important source of evidence for the events of the Nanjing massacre.Nakaijma was subsequently at the Battle of Wuhan before being transferred to take command of the Japanese Fourth Army in Manchukuo from 1938 to 1939.