By the beginning of World War II, Aruga was commander of Destroyer Division 4. At the June 1942 Battle of Midway, Aruga's destroyers screened Vice Admiral Nagumo Chuichi's 1st Carrier Striking Force. Two months later, Aruga still commanded Destroyer Division 4 and participated in the Battle of the Eastern Solomons, screening Admiral Abe Hiroaki's Vanguard Group.
In March 1943, Aruga took command of the cruiser Chokai. In July 1944, he was appointed head of the Torpedo School. On 25 November 1944, Aruga, now a rear admiral, assumed command of the battleship Yamato. Her war record had been undistinguished, and as flagship of the Combined Fleet she had often remained far from the action. The Yamato had been damaged by a torpedo from the American submarine Skate on 25 December 1943, and her only surface action had been in the battle off Samar in October 1944 against American escort carriers.
On 1 April 1945, U.S. forces landed on Okinawa. Taunted by his army counterpart that the Yamato was a floating hotel for idle and inept admirals, commander of the Combined Fleet Admiral Toyoda Soemu drafted orders for Operation ichi-ten. The Yamato was provided sufficient fuel for a one-way trip to Okinawa. Escorted by one light cruiser and eight destroyers, the Yamato was to draw off American carrier planes, leaving the American fleet vulnerable to a mass attack by kamikazes. The Yamato would then destroy the American transports off Okinawa and beach herself to serve as an unsinkable fortress. Her crew was then to join the fighting on land.
When the task force commanders learned of the orders, they protested. Although they were willing to die for Japan, they did not believe the plan would produce significant results. They wanted instead to attack U.S. lines of communication. When Second Fleet Commander Vice Admiral Ito Seiichi, who took command of the operation aboard the Yamato, refused to change the orders, Aruga and the other commanders accepted their fate. Aruga was overheard to state, "What a glorious way to die!"
The Yamato sortied the afternoon of 6 April. Cadets and ill sailors were landed before she left. U.S. forces located the Yamato early the next morning and pounded her with waves of carrier planes. She was hit by at least seven bombs and 11–15 torpedoes. When flooding caused a serious list to port, Aruga ordered counterflooding, although many men were trapped below decks. By 2:00 p.m., Aruga realized the end was near. He ordered that Emperor Hirohito's portrait be saved and had himself tied to the compass mounting to avoid surviving the sinking of his ship. At 2:23 p.m., the Yamato rolled onto an even keel and exploded. Aruga and Ito were not among the 269 survivors of the Yamato's 2,767-man crew. Aruga was posthumously promoted to vice admiral. Tim J. Watts
Dull, Paul S. A Battle History of the Imperial Japanese Navy (1941–1945). Annapolis, MD: Naval Institute Press, 1978.; O'Neill, Richard. Suicide Squads: Axis and Allied Special Attack Weapons of World War II: Their Development and Their Missions. London: Salamander Books, 1981.; Spurr, Russell. A Glorious Way to Die: The Kamikaze Mission of the Battleship "Yamato," April 1945. New York: Newmarket Press, 1981.; Yoshida, Mitsuru. Requiem for Battleship "Yamato." Trans. Richard Minear. Seattle: University of Washington Press, 1985.
Tim J. Watts