Organization The 7th Defense Battalion was commissioned on 16 December 1940 at
Marine Corps Base San Diego,
California. From 16 December through 26 February 1941 the battalion focused on organizing, equipping and training for future employment. The battalion was organized differently then the other defense battalions at the time which were optimized for coastal and air defense. The 7th originally lacked the air defense capability and was composed of a headquarters company, an infantry company (Company A), and an artillery company (Company B).
American Samoa Prior to the battalion even being formed an advanced party had been sent to
Pago Pago on
Tutuila to scout out locations. It arrived on 21 December 1940. On 27 February the battalion's main body embarked on the
USS William P. Biddle (APA-8) at San Diego and sailed for Tutuila,
American Samoa with a stop at
Pearl Harbor on the way. The main body of the 7th Defense Battalion arrived at Tutuila on 18 March 1941. This made the battalion the first unit of the
Fleet Marine Force to ever operate in the South Pacific. The next few weeks saw the battalion heavily engaged in camp construction and the installation of artillery emplacements. In April 1941, after coming out of measles quarantine, the 7th Defense Battalion moved to
Faga'alu and began construction of Camp Samuel Nicholas. In May 1941 authority was granted for the raising of a reserve native Samoan Battalion. The 1st Samoan Battalion was commissioned on 1 July 1941 and Marines from the 7th Defense Battalion were responsible for organizing and training these new recruits. On 7 December 1941 the battalion was informed about the
attack on Pearl Harbor via a radio and immediately went to
general quarters. The battalion's first exposure to combat occurred at 2:30AM on 11 January 1942 when a Japanese submarine surfaced and began shelling the Naval Station on Tutuila for approximately seven minutes. The 7th Defense Battalion, with the 1st Samoan Brigade attached, remained the sole defensive unit on Tutuila until 21 January 1942 when the island was reinforced by the 2nd Marine Brigade. Upon the brigade's arrival, the 7th Defense Battalion fell under its command. Maintaining the position on Tutuila was critical to ensuring that the lines of communication between Hawaii and
Australia remained open.
Movement to Upolu, Hawaii and Nanomea On 28 March 1942 the 7th Defense Battalion departed Tutuila onboard the
SS President Garfield bound for the island of
Upolu in
Samoa. The battalion reinforced a small garrison of New Zealanders. Later on the battalion also establish a position on
Savai'i. Savai'i was too mountainous for an airfield and the harbor was not deep enough for an anchorage however the detachment was needed for internal island security. On 9 May 1942 the battalion fell under the command of the
3rd Marine Brigade. Beginning on 12 August 1943, the battalion left
Apia Harbor in three successive waves headed for
Nanumea, the northernmost of the
Ellice Islands. The first detachment arrived on 14 August 1943 in order to occupy, organize, and defend the
airfield that was being constructed by the
16th Naval Construction Battalion. On 10 November 1943 the battalion downed one Japanese bomber of a force of twelve that were sent to bomb the airfield. On 26 December 1943, E Battery was detached for duty with the
8th Defense Battalion on
Apamama in the
Gilbert Islands. The battalion remained on Nanumea until February 1944 when they were relieved by the
51st Defense Battalion. The battalion departed Nanumea on 9 March 1944 arriving at
Kauai on 21 March 1944. As the war progressed, the Marine Corps removed coastal artillery from the defense battalions in order to form additional heavy artillery units for the
Fleet Marine Force. Because of the divestiture of the coastal defense mission, the battalion was re-designated as the 7th Antiaircraft Artillery Battalion on 16 April 1944.
Battle of Angaur, garrison duty and decommissioning The assault echelon of the newly reorganized 7th Antiaircraft Artillery Battalion departed Kauia on 7 August 1944. The battalion had been tasked with installing, operating and maintaining and air warning system in support of the
United States Army's 81st Infantry Division during the assault on
Angaur. Angaur was part of the larger operation to dislodge the Japanese from the
Palau Islands. The main body of the advance echelon went ashore on Angaur on 24 September 1944. On 11 November 1944 the 7th AAA Battalion became part of the Army Garrison Force on the island. The 7th AAA Battalion remained on Angaur as the garrison force until it was relieved of its mission on 12 July 1945. The battalion's personnel were transferred to the United States or other units in theater and the battalion was officially decommissioned 2 August 1945 on
Guam. == Unit awards ==