Battle of the Tenaru Story Brief

On August 7, 1942, U.S. forces landed on Guadalcanal, Tulagi, and Florida Islands in the Solomon Islands. The landings on the islands were meant to deny their use by the Japanese as bases for threatening the supply routes between the U.S. and Australia, and to secure the islands as starting points for a campaign with the eventual goal of isolating the major Japanese base at Rabaul while also supporting the Allied New Guinea campaign. The landings initiated the six-month-long Guadalcanal campaign.

Taking the Japanese by surprise, the Allied landing forces accomplished their initial objectives of securing Tulagi and nearby small islands, as well as an airfield under construction at Lunga Point on Guadalcanal, by nightfall on August 8. That night, as the transports unloaded, the Allied warships screening the transports were surprised and defeated by an Imperial fleet of seven cruisers and one destroyer, commanded by Japanese Vice Admiral Gunichi Mikawa. One Australian and three U.S. cruisers were sunk and one other U.S. cruiser and two destroyers were damaged in the Battle of Savo Island. Turner withdrew all remaining Allied naval forces by the evening of August 9 without unloading all of the heavy equipment, provisions, and troops from the transports, although most of the divisional artillery was landed, consisting of thirty-two 75 mm and 105 mm howitzers. Only five days worth of rations were landed.

The Marines ashore on Guadalcanal initially concentrated on forming a defence perimeter around the airfield, moving the landed supplies within the perimeter, and finishing the airfield. Vandegrift placed his 11,000 troops on Guadalcanal in a loose perimeter around the Lunga Point area. In four days of intense effort, the supplies were moved from the landing beach into dispersed dumps within the perimeter. Work began on the airfield immediately, mainly using captured Japanese equipment. On August 12, the airfield was named Henderson Field after Major Lofton Henderson, a Marine aviator who had been killed at the Battle of Midway. Captured Japanese stock increased the total supply of food to 14 days worth. To conserve the limited food supplies, the Allied troops were limited to two meals per day.

Japanese Colonel Kiyonao Ichiki, commander of the 28th Infantry Regiment.
In response to the Allied landings on Guadalcanal, the Japanese Imperial General Headquarters assigned the Imperial Japanese Army's 17th Army, a corps-sized command based at Rabaul and under the command of Lieutenant-General Harukichi Hyakutake, with the task of retaking Guadalcanal from Allied forces. The 17th Army, currently heavily involved with the Japanese campaign in New Guinea, had only a few units available to send to the southern Solomons area. Of these units, the 35th Infantry Brigade under Major General Kiyotake Kawaguchi was at Palau, the 4th (Aoba) Infantry Regiment was in the Philippines, and the 28th (Ichiki) Infantry Regiment, under the command of Colonel Kiyonao Ichiki, was at sea en route to Japan from Guam. The different units began to move towards Guadalcanal immediately, but Ichiki's regiment, being the closest, arrived first.

An aerial reconnaissance of the U.S. Marine positions on Guadalcanal on August 12 by one of the senior Japanese staff officers from Rabaul sighted few U.S. troops in the open and no large ships in the waters nearby, convincing Imperial Headquarters that the Allies had withdrawn the majority of their troops. In fact, none of the Allied troops had been withdrawn. Hyakutake issued orders for an advance unit of 900 troops from Ichiki's regiment to be landed on Guadalcanal by fast warship to immediately attack the Allied position and reoccupy the airfield area at Lunga Point. The remaining personnel in Ichiki's regiment would be delivered to Guadalcanal by slower transport later. At the major Japanese naval base at Truk, which was the staging point for delivery of Ichiki's regiment to Guadalcanal, Colonel Ichiki was briefed that 2,000–10,000 U.S. troops were holding the Guadalcanal beachhead and that he should, "avoid frontal attacks."[16]

Ichiki and 916 of his regiment's 2,300 troops, designated the "First Element" and carrying seven days' supply of food, were delivered to Taivu Point, about 35 kilometers (22 miles) east of Lunga Point, by six destroyers at 01:00 on August 19.[17] Ichiki was ordered to scout the American positions and wait for the remainder of his force to arrive. Known as the Ichiki Butai (Ichiki Detachment), they were an elite and battle-seasoned force but as was about to be discovered, they were heavily stricken with "victory disease" – overconfidence due to previous success.

August 21, 1942 on the island of Guadalcanal

Will the might of the IJA be enough to retake the Airfield or will the Marines hold it and repell all Japanese attacks ...