He attended military preparatory schools and was a graduate of the 20th class of the Imperial Japanese Army Academy in 1908.

He was assigned to the IJA's 44th Infantry Regiment, and served during Japan's Siberian Intervention against Bolshevik forces in eastern Russia.

After having risen steadily through the ranks, Inoue was commissioned as a major general in March 1939 and became commander of the IJA 33rd Division.

Both Inoue and Tōjō knew that the 14th division would not be able to hold the island group against the numerically superior Allied forces, but the Japanese government felt that it was critical to defend the islands to the death, which would result in a Pyrrhic victory for the Allies and would serve to discourage further invasions of the Japanese South Seas Mandate.

[3] After the war, Inoue was arrested by the American occupation authorities and deported to Guam, where he was tried for Class B and Class C war crimes and condemned to death in 1949 for negligence of command responsibility in permitting subordinates to execute three downed American airmen captured in Palau.