Organization The 7th Defense Battalion was commissioned on June 1, 1942, at
Marine Corps Base San Diego,
California. Lieutenant Colonel
Robert Blake was the battalion's first commanding officer. At commissioning the battalion consisted of the following elements: • H&S Battery • 155mm Artillery Group • 90mm AA Group • Special Weapons Group
Russell Islands On August 21, 1942, the battalion embarked on the and sailed for the
Territory of Hawaii. They arrived at
Pearl Harbor on August 31, 1942, and proceeded to establish themselves at nearby Camp Catlin. Not long for Hawaii, the battalion departed on February 6 on board the and the . After a layover in
Espiritu Santo they arrived at the
Florida Islands on February 24, 1943. The first echelon of the battalion departed on March 14 for the
Russell Islands. The remainder of the battalion arrived by March 28, 1943. "A" Battery was located on
Pavuvu while "B" Battery was stationed on
Mbanika. Originally the battalion established an
SCR-270 radar on a mountain on Mbanika. Problems supplying the radar and moisture caused by cloud cover caused it to be moved to a hill on the northeast portion of the island. During May and June 1943, antiaircraft guns of the 10th Defense Battalion engaged numerous Japanese air raids against the newly constructed
airfield on
Banika. During this time the Commanding Officer of the 10th Defense Battalion also assumed the responsibilities as the
Antiaircraft Commander, Russell Islands and
Commander Marine Defense Group Solomons. During July 1943,
M3A1 Stuart Light Tanks of the 10th Defense Battalion were assigned to support the
43rd Infantry Division securing
Munda Point on
New Georgia. After Munda, the tank section was transported via landing craft to
Arundel Island where they again provided fire support for the 43rd Infantry during their seizure of the island. On December 30, 1943, the
US Army's 13th Antiaircraft Group assumed responsibility for air and coastal defense of the Russell Island.
Eniwetok From February 1–7 the battalion loaded on board the and the . The ships departed the Russell Islands on February 10 and arrived at
Tarawa, where it received verbal orders to proceed to
Kwajalein Atoll. Upon arrival off the coast of Kwajalein on February 18 the battalion received orders to organize a 500-man infantry unit (10th Defense Battalion Provisional Landing Force). It was going to serve as the
V Amphibious Corps reserve for the upcoming assault on the atoll. The 10th did not land on D-Day as Marines from the
22nd Marine Regiment accomplished the mission on February 22. The battalion went ashore on
Eniwetok on February 24 and began set up air and coastal defense guns. It assumed responsibility for air defense of Eniwetok along with
Air Warning Squadron 1 whose Air Defense Control Center provided
early warning radar and
Ground-controlled interception for fighters.
Reorganization, Hawaii and decommissioning 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 10th Antiaircraft Artillery Battalion on May 31, 1944. The seacoast artillery section departed Eniwetok on August 29 sailing for Kauai, Hawaii. Shortly thereafter on September 16 the
51st Defense Battalion assumed responsibility for defense of Eniwetok and Parry Islands. The 10th Antiaircraft Artillery Battalion departed the
Marshall Islands on September 17 and arrived in Kauai on September 27, 1944. The 10th Antiaircraft Artillery Battalion was decommissioned on November 25, 1944, by authority of
Fleet Marine Force, Pacific Special Order Number 104-44. ==Unit awards==