 In the Battle of the Tenaru, the firepower provided by del Valle's artillery units killed many assaulting Japanese soldiers—almost to the last man—before they reached the Marine positions.As a result of the outcome of the battle the Japanese commander, Colonel Kiyonao Ichiki, committed seppuku shortly afterwards.General Alexander Vandegrift, impressed with del Valle's leadership, recommended his promotion and on October 1, 1942, del Valle became a brigadier general.