The 12th Antiaircraft Artillery Battalion (12th AAA Bn) was a

United States Marine Corps The United States Marine Corps (USMC), also referred to as the United States Marines, is the maritime land force service branch of the United States Armed Forces responsible for conducting expeditionary and amphibious operations through combi ...

antiaircraft Anti-aircraft warfare, counter-air or air defence forces is the battlespace response to aerial warfare, defined by NATO as "all measures designed to nullify or reduce the effectiveness of hostile air action".AAP-6 It includes surface based, ...

unit that served during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

. Formed in 1942 as the 12th Defense Battalion, its original mission was providing air and coastal defense for advanced naval bases. During the war the battalion defended the

Russell Islands :''See also Russell Island (disambiguation).'' The Russell Islands are two small islands (Pavuvu and Mbanika), as well as several islets, of volcanic origin, in the Central Province of Solomon Islands. They are located approximately northwest of ...

and took part in combat operations at

Woodlark Island Woodlark Island, known to its inhabitants simply as Woodlark or Muyua, is the main island of the Woodlark Islands archipelago, located in Milne Bay Province and the Solomon Sea, Papua New Guinea. Although no formal census has been conducted sinc ...

, Cape Gloucester, and

Peleliu Peleliu (or Beliliou) is an island in the island nation of Palau. Peleliu, along with two small islands to its northeast, forms one of the sixteen states of Palau. The island is notable as the location of the Battle of Peleliu in World War II. H ...

. The battalion remained on Peleliu for the duration of the war and was finally decommissioned on

Guam Guam (; ch, Guåhan ) is an organized, unincorporated territory of the United States in the Micronesia subregion of the western Pacific Ocean. It is the westernmost point and territory of the United States (reckoned from the geographic cent ...

on 22 September 1945.

History

The 12th Defense Battalion was commissioned on August 1, 1942 at

San Diego San Diego ( , ; ) is a city on the Pacific Ocean coast of Southern California located immediately adjacent to the Mexico–United States border. With a 2020 population of 1,386,932, it is the List of United States cities by population, eigh ...

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

. On January 19, 1943 the battalion embarked on the USS Pinkney and the SS Robin Wentley and sailed for the

Territory of Hawaii The Territory of Hawaii or Hawaii Territory ( Hawaiian: ''Panalāʻau o Hawaiʻi'') was an organized incorporated territory of the United States that existed from April 30, 1900, until August 21, 1959, when most of its territory, excluding ...

. It arrived at

Pearl Harbor Pearl Harbor is an American lagoon harbor on the island of Oahu, Hawaii, west of Honolulu. It was often visited by the Naval fleet of the United States, before it was acquired from the Hawaiian Kingdom by the U.S. with the signing of the Re ...

on January 29 and immediately set up camp at and began training at Camp Catlin on Oahu. The battalion sailed from Pearl Harbor on May 14, 1943 on board the SS Robin Wentley. They arrived at

Townsville Townsville is a city on the north-eastern coast of Queensland, Australia. With a population of 180,820 as of June 2018, it is the largest settlement in North Queensland; it is unofficially considered its capital. Estimated resident population, 3 ...

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

on 1 June however it was not there long. The 12th Defense Battalion departed Australia on 13 June en route to their objective area. Between 30 June and 1 July the battalion landed at

and

Milne Bay Milne Bay is a large bay in Milne Bay Province, south-eastern Papua New Guinea. More than long and over wide, Milne Bay is a sheltered deep-water harbor accessible via Ward Hunt Strait. It is surrounded by the heavily wooded Stirling Range to t ...

. Their mission was to provide area air defense for the

United States Army The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cla ...

units tasked with seizing these islands. The battalion remained at Woodlark Island until December 7, 1943 when it set departed for

Oro Bay Oro Bay is a bay in Oro Province, Papua New Guinea, located southeast of Buna, Papua New Guinea, Buna. The bay is located within the larger Dyke Ackland Bay. A port is operated by PNG Ports Corporation Limited with limited wharf facilities, loca ...

New Guinea New Guinea (; Hiri Motu Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea). It is a simplified version of ...

. The 12th Defense Battalion came ashore on Cape Gloucester between 26 & 27 December 1943. Once ashore the battalion was initially tasked with establishing air and seacoast defense of Beaches Yellow 1 & 2. As the battalion was unloading on 26 December the first Japanese air raids occurred. A few hastily placed guns let loose against 88 Japanese aircraft that were strafing and bombing the beachhead. With no real threat of an amphibious counterattack, the battalion's coastal guns were utilized for deep fired against Japanese supply ships and staging areas. The battalions radars and guns provided

early warning An early warning system is a warning system that can be implemented as a Poset, chain of information communication systems and comprises sensors, Detection theory, event detection and decision support system, decision subsystems for early identi ...

and anti-aircraft fires against Japanese planes flying out of

Rabaul Rabaul () is a township in the East New Britain province of Papua New Guinea, on the island of New Britain. It lies about 600 kilometres to the east of the island of New Guinea. Rabaul was the provincial capital and most important settlement in ...

that continued to harass the beachhead over the next few months. A majority of the battalion departed Cape Gloucester via the SS Santa Monica on 1 June 1944. It arrived at

Banika Mbanika or Banika is an island in Solomon Islands; it is located in the Central Province and is the second largest of the Russell Islands Group. The principal settlement is Yandina. As portrayed in the HBO miniseries, '' The Pacific'', episod ...

in the

on 9 June. 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 The United States Fleet Marine Forces (FMF) are combined general- and special-purpose forces within the United States Department of the Navy that perform offensive amphibious or expeditionary warfare and defensive maritime employment. The Fleet ...

. Because of the divestiture of the coastal defense mission, the battalion was re-designated as the 12th Antiaircraft Artillery Battalion on 15 June 1944. At the end of August 1944 the battalion participated in landing rehearsals at

Guadalcanal Guadalcanal (; indigenous name: ''Isatabu'') is the principal island in Guadalcanal Province of Solomon Islands, located in the south-western Pacific, northeast of Australia. It is the largest island in the Solomon Islands by area, and the seco ...

and on 8 September they set sail for Peleliu. The battalion went ashore at Peleliu on 15 September 1944 and, along with the

7th Antiaircraft Artillery Battalion The 7th Antiaircraft Artillery Battalion (7th AAA Bn) was a United States Marine Corps antiaircraft unit that served during World War II. Formed in 1940 as the 7th Defense Battalion, its original mission was to provide air and coastal defense for ...

was tasked with providing air defense for the landing force once ashore. The battalion guns were also utilized in direct fire mission in support of Marine assault forces attempting to dislodge dug in Japanese defenders. After the battle, the battalion remained on Peleliu for the duration of the war. In March 1945, the unit's heavy guns section was sent to the northern Palau Islands in order to engage enemy targets. On 13 September 1945 the 12th AAA Battalion departed Peleliu arriving on

on 16 September. On 22 September 1945 the battalion was decommissioned on Guam.

Unit awards

A unit citation or commendation is an award bestowed upon an organization for the action cited. Members of the unit who participated in said actions are allowed to wear on their uniforms the awarded unit citation. The 12th Antiaircraft Artillery Battalion has been presented with the following awards: Memorial for the members of the 12th Defense Battalion lost during WW2. It is located inside the MCRD, San Diego, CA *

Marine Defense Battalions Marine Defense Battalions were United States Marine Corps battalions charged with coastal and air defense of advanced naval bases during World War II. They maintained large anti-ship guns, anti-aircraft guns, searchlights, and small arms to repe ...

List of United States Marine Corps aviation support units This is a list of United States Marine Corps aviation support squadrons and other units, sorted by type. Active Marine Wing Headquarters Squadrons The Marine Wing Headquarters Squadron (MWHS) provides administrative and supply support for a Mari ...

Citations

References

;Bibliography * * * * ;Web * Part 1 * Part 2 {{US Marine Corps navbox AAA12 Military units and formations established in 1942

AAA AAA, Triple A, or Triple-A is a three-letter initialism or abbreviation which may refer to: Airports * Anaa Airport in French Polynesia (IATA airport code AAA) * Logan County Airport (Illinois) (FAA airport code AAA) Arts, entertainment, and me ...

Military units and formations of the United States Marine Corps in World War II