In his early career, Tanabe served on the staff of the
Kyoto-based
IJA 16th Division, as an instructor at the Army Academy, as a
military attaché to France, commander of the IJA 61st Infantry Battalion, and on the staff of the Army Maintenance Bureau. After serving as instructor at the Toyama Army Infantry School from 1933 to 1934, Tanabe served as Chief of the Economic Mobilization Section in the
Army Ministry. He returned to the field to command the IJA 34th Infantry Regiment from 1936 to 1937, before his promotion to major general in August 1937 and returning to the Toyama Army Infantry School as its commandant. With the outbreak of the
Second Sino-Japanese War, Tanabe was appointed
Chief of Staff of the
IJA 10th Army in October 1937. This was a new organization under the
Japanese Central China Area Army, created as an emergency reinforcement force to supplement the Japanese
Shanghai Expeditionary Army after the
Second Shanghai Incident. The Japanese 10th Army subsequently participated in the
Battle of Nanking and the subsequent atrocities known as the
Nanjing Massacre. The unit was officially disbanded in
Nanjing on February 14, 1938. Tanabe was recalled to Japan to become commandant of the IJA Tank School, located in
Chiba. Tanabe was promoted to lieutenant general in October 1939, and given command of the
IJA 41st Division. This was also a new organization, raised in
Yongsan District,
Korea, and was assigned to
1st Army as a garrison force in Japanese-occupied
Shanxi Province. From March to November 1941, he was Chief of Staff of the
Japanese Northern China Area Army. Tanabe was recalled to Japan at the end of 1941 to serve as Vice Chief of the
Imperial Japanese Army General Staff, and was in this position at the time of the
attack on Pearl Harbor, which he had strenuously opposed. Once the war began, he favored a defensive strategy of luring the
Allies into campaigns in areas away from their bases in hopes of stretching their supply lines to Japan's advantage. He was instrumental in helping put an end to the disastrous attrition of Japanese forces at
Guadalcanal. As conditions began to deteriorate for Japan along its southern front in the
Pacific War, Tanabe was dispatched in April 1943 to
Japanese-occupied Sumatra in the
Netherlands East Indies to take command of the
IJA 25th Army under the
Japanese Seventh Area Army at
Fort de Kock. He remained at this post for the remainder of the war. Tanabe had reservations about the increasing role of the Indonesian nationalist movement on
Java but, responding to the “Koiso Promise” granting increased autonomy and eventual independence to Indonesia, he established the Sumatra Central Advisory Committee and trained locals for administrative leadership roles. However, he attempted to distance himself from local politics by as much as possible. At the end of the war, he was arrested by Dutch authorities and was sent to
Medan where he faced a Dutch
military tribunal which accused him of unspecified
war crimes. He was
sentenced to death on 30 December 1948 and executed on 10 July 1949. ==Decorations==