Lineage

• Constituted 19 September 1952 in the Army Reserve
  United States Army Reserve
  The United States Army Reserve is the federal reserve force of the United States Army. Together, the Army Reserve and the Army National Guard constitute the reserve components of the United States Army....
  
   as Headquarters and Headquarters Detachment, 309th Communication Reconnaissance Battalion.
• Activated 1 November 1952 at Los Angeles.
• Reorganized and redesignated 25 January 1956 as Headquarters and Headquarters Company, 309th Communication Reconnaissance Battalion (organic elements constituted 29 December 1955 – 4 March 1956 and activated 1 February 1956 – 5 March 1956).
• Redesignated 1 October 1956 as the 309th Army Security Agency Battalion.
• Inactivated 15 July 1959 at Los Angeles.
• Activated 15 September 1962 with Headquarters at Bell, California
  Bell, California
  Bell is a city in Los Angeles County, California. Its population was 35,477 at the 2010 census, down from 36,664 in the 2000 census. Bell is located on the west bank of the Los Angeles River and is a suburb of the city of Los Angeles...
  
  .
• Companies A, B, C, and D reorganized and redesignated 15 August 1966 as the 518th, 519th, 520th, and 521st Army Security Agency Companies – hereafter separate lineages.
• Headquarters and Headquarters Company Inactivated 15 July 1986 at Bell, California
  Bell, California
  Bell is a city in Los Angeles County, California. Its population was 35,477 at the 2010 census, down from 36,664 in the 2000 census. Bell is located on the west bank of the Los Angeles River and is a suburb of the city of Los Angeles...
  
  .
• Redesignated 1 February 1990 as Headquarters and Headquarters Company, 309th Military Intelligence Battalion; concurrently withdrawn from the Army Reserve
  United States Army Reserve
  The United States Army Reserve is the federal reserve force of the United States Army. Together, the Army Reserve and the Army National Guard constitute the reserve components of the United States Army....
  
   and allotted to the Regular Army
  Regular Army
  The Regular Army of the United States was and is the successor to the Continental Army as the country's permanent, professional military establishment. Even in modern times the professional core of the United States Army continues to be called the Regular Army...
  
  .
• Headquarters transferred 17 August 1990 to the United States Army Training and Doctrine Command
  United States Army Training and Doctrine Command
  Established 1 July 1973, the United States Army Training and Doctrine Command is an army command of the United States Army headquartered at Fort Eustis, Virginia. It is charged with overseeing training of Army forces, the development of operational doctrine, and the development and procurement of...
  
   and activated at Fort Huachuca
  Fort Huachuca
  Fort Huachuca is a United States Army installation under the command of the United States Army Installation Management Command. It is located in Cochise County, in southeast Arizona, about north of the border with Mexico. Beginning in 1913, for 20 years the fort was the base for the "Buffalo...
  
  , Arizona
  Arizona
  Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
  
   as an element of the United States Army Intelligence Center
  United States Army Intelligence Center
  The United States Army Intelligence Center of Excellence is the United States Army's school for professional training of military intelligence personnel...
  
  's 111th Military Intelligence Brigade.

Current Mission

• Company A (nicknamed "Panthers") support and train counterintelligence students in the Counterintelligence Special Agent Course (CISAC). In addition, the company provide administrative and logistical support staff to the battalion.

• Company B (nicknamed "Bulldogs") support and train Linguist students in the Linguist(MOS 09L) Course.

• Company E (nicknamed "Eagles") support and train human intelligence students in the Human Intelligence Collector (MOS 35M) Course.

• Company F (nicknamed "Death Dealers") support and train human intelligence students in the Human Intelligence Collector (MOS 35M) Course.

Distinctive Unit Insignia

• Description: A gold color metal and enamel device 1 5/32 inches (2.94 cm) in height overall, consisting of a shield blazoned as follows: Argent, on a pale emitting in saltire four lightning flashes Azure (Teal Blue) a key bit to dexter in base, the bow a bear’s head, Or. Attached above the shield is a Gold triparted scroll inscribed “Sentinels of Security” in black letters.

• Symbolism: Teal blue and silver refer to the colors formerly used for the U.S. Army Security Agency. The key symbolizes the unit’s mission which is providing security. The golden bear’s head on the key represents California where the unit activated. The lightning flashes, symbolizing electricity, relate to the importance of electronic communications as part of the unit’s functions.

• Background: The distinctive unit insignia was originally approved for the 309th Army Security Agency Battalion, Army Reserve on 12 February 1959. It was assigned for use by the 325th U.S. Army Security Agency Battalion on 5 August 1959. It was reassigned for the 309th U.S. Army Security Agency Battalion on 2 August 1965. The insignia was redesignated for the 309th Military Intelligence Battalion on 2 May 1990.

Coat of Arms

• Shield: Argent, on a pale emitting in saltire four lightning flashes Azure (Teal Blue) a key ward to dexter in base, the bow a bear’s head, Or.

• Crest:
  • 1990–present: None.
  • 1959–1986: That for the regiments and separate battalions of the Army Reserve: On a wreath of the colours, argent and azure, the Lexington Minuteman proper. The statue of the Minuteman, Capt. John Parker
    John Parker (Captain)
    John Parker was an American farmer, mechanic, and soldier, who commanded the Lexington militia at the Battle of Lexington on April 19, 1775. Parker was born in Lexington to Josiah Parker and Anne Stone...
    
     (Henry Hudson Kitson
    Henry Hudson Kitson
    Sir Henry Hudson Kitson, often known as H. H. Kitson, American sculptor, born in Huddersfield, England on April 9, 1865 and died at Tyringham, Massachusetts, on June 26, 1947...
    
    , sculptor), stands on the Common in Lexington, Massachusetts
    Lexington Battle Green
    The Lexington Battle Green, properly known as Lexington Common, is the site of the opening shots of the American Revolution in 1775 during the Battle of Lexington. The Common had been purchased by subscription of some of the town's leading citizens in 1711...
    
    .

• Motto: “Sentinels of Security”.

• Symbolism: Teal blue and white were the colors used for the U.S. Army Security Agency, the original designation of the organization. The key symbolizes the unit’s mission—the guarding of security—and the golden bear’s head on the key represents the State of California, where the unit was activated. The lightning flashes, symbolic of electricity, relate to the importance of electronic communications as part of the unit’s functions.

• Background: The coat of arms was originally approved for the 309th Army Security Agency Battalion, Army Reserve, on 12 February 1959. It was assigned for use by the 325th U.S. Army Security Agency Battalion, Army Reserve on 5 August 1959. It was reassigned for use by the 309th U.S. Army Security Agency Battalion on 2 August 1965. It was cancelled on 6 June 1975. The coat of arms was reinstated and redesignated for the 309th Military Intelligence Battalion on 10 October 1995.