The 3rd Air Defense Artillery Regiment is an air defense artillery regiment of the United States Army, first formed in 1821 as the 3rd Regiment of Artillery.
History
Constituted 1 June 1821 in the Regular Army as the 3rd Regiment of Artillery and organized from existing units with headquarters at Fort Washington, Maryland. The lineages of some of the units that initially made up the 3rd U.S. Artillery include campaign credit for the War of 1812.
Twelve batteries of the 3rd U.S. Artillery served in the American Civil War.
Four batteries of the 3rd U.S. Artillery were assigned to Fort Jefferson, Florida in 1869.
The 1st and 2nd Battalions of the regiment deployed to the Philippines in the Spanish–American War of 1898, while Battery F deployed to Puerto Rico.
Regiment broken up 13 February 1901 and its elements reorganized and redesignated as separate numbered companies and batteries of the Artillery Corps.
Reconstituted 1 July 1924 in the Regular Army as the 3rd Coast Artillery (Harbor Defense) (Type B) and organized (less Batteries C, F, and G) with headquarters, 1st Battalion, and Batteries A & B at Fort MacArthur, California in the Harbor Defenses of Los Angeles. The regiment was organized by redesignating the 25th, 26th, 27th, 28th, 31st, 34th, 35th, and 36th companies of the Coast Artillery Corps (CAC). Batteries A, B, D, and E carried the lineage and designations of the corresponding batteries in the old 3rd Artillery. HHB 2nd Battalion and Battery D at Fort Rosecrans, California (HD San Diego) (Battery C inactive), and HHB 3rd Battalion and Battery E at Fort Stevens, Oregon (HD of the Columbia River) (Batteries F & G inactive).
The Oregon National Guard component of HD Columbia River was the 249th Coast Artillery from 1924 until October 1944, and the California National Guard component of HD Los Angeles and HD San Diego was the 251st Coast Artillery from 1924 until January 1930.
Batteries A and B inactivated 1 March 1930 at San Pedro and Fort MacArthur, California, respectively; Batteries A and F activated 1 July 1939 at Fort MacArthur and Fort Stevens, respectively; Battery D inactivated 1 February 1940 at Fort Rosecrans (replaced by Battery A, 19th Coast Artillery), with Batteries E & F inactivated at Fort Stevens (they became Batteries A & B, 18th Coast Artillery); Battery B activated 1 July 1940 at Fort MacArthur; Batteries C, D, E, and F activated 2 December 1940 at Fort MacArthur; Batteries B & D exchanged designations mid-December 1940; Battery G (searchlight battery) activated 1 June 1941 at Los Angeles, California; Battery G inactivated 29 August 1941 at Los Angeles; Battery G activated 14 February 1942 at Fort MacArthur; Batteries C & D exchanged designations 1 October 1942.
Regiment reorganized as Type A 21 August 1941.
Regiment broken up 18 October 1944 and its elements reorganized and redesignated as follows:
Headquarters and Headquarters Battery as Battery B, 521st Coast Artillery Battalion.
1st, 2nd, and 3rd Battalions as the 520th, 521st, and 522nd Coast Artillery Battalions, respectively.
After 18 October 1944 the above units underwent changes as follows:
520th CA Battalion redesignated as 3rd CA Battalion 1 December 1944.
3rd CA Battalion, 521st CA Battalion, and 522nd CA Battalion, disbanded 15 September 1945 at Fort MacArthur, California.
Reconstituted 28 June 1950 in the Regular Army and redesignated as Headquarters and Headquarters Battery, 3rd Antiaircraft Artillery Group. Activated 11 June 1951 at Camp Stewart, Georgia.
Redesignated 20 March 1958 as Headquarters and Headquarters Battery, 3rd Artillery Group. Inactivated 15 December 1961 at Norfolk, Virginia.
520th Coast Artillery Battalion redesignated 1 December 1944 as the 3rd Coast Artillery Battalion. Disbanded 15 September 1945 at Fort MacArthur, California. Reconstituted 20 January 1950 in the Regular Army; concurrently consolidated with the 3rd Antiaircraft Artillery Automatic Weapons Battalion (active) (see ANNEX 1) and consolidated unit designated as the 3rd Antiaircraft Artillery Automatic Weapons Battalion, an element of the 3rd Infantry Division. Redesignated 15 April 1953 as the 3rd Antiaircraft Artillery Battalion. Inactivated 1 July 1957 at Fort Benning, Georgia, and relieved from assignment to the 3rd Infantry Division.