ASA operations in Korea began in mid September 1950 when the first ASA element (an eight man detachment)
arrived. They were followed at the end of November by ASA Pacific (Advance), many of whom came from the 126th
Signal Service Company at Kyoto. At the end of October the first sizable ASA component, the 60th Signal Service
Company from Fort Lewis arrived in Korea. In June 1951, the 303rd Communications Reconnaissance Battalion
(CRB) arrived and co-located with ASA Pacific (Advance) and assumed duties as the ASA theater command and
control. The 501st CR Group became operational in July 1951, having been ordered to Korea from Camp Pickett,
Virginia. It’s mission was to support Eighth U.S. Army. ASA Pacific (Advance) was absorbed by the 501st.

The ASA was revitalized by the Korean War. Previously, most ASA assets had been concentrated at fixed sites,
performing a peacetime strategic mission. The Agency now found a new role in providing support to tactical
operations, activating Communications Recon Groups, battalions and companies to support Commanders at every
level. ASA SIGINT efforts were hampered by the problem of a lack of Chinese linguists.

ASA Units In Korea
•  126th Signal Service Co
•  226th Signal Service Co
•  301st Communications Recon Bn
•  303rd Communications Recon Bn
•  304th Communications Recon Bn
•  326th Communications Recon Co
•  329th Communications Recon Co
•  330th Communications Recon Co
.  351st Communications Recon Co
•  352nd Communications Recon Co
•  501st Army Security (Com Recon Group)
•  50th Signal Service Detachment
•  60th Army Security Co / 60th Signal Service Co
Submitted by Sandy Helfand, ASA Korea Member
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501st MI Brigade History

Constituted on 13 October 1950 in the Regular Army as HHC, 501st Communication Reconnaissance Group, the unit
was activated on 20 October 1950 at Camp Pickett, Virginia, and assigned to the Army Security Agency.

On 29 May 1951, the 501st Transferred from Camp Pickett to Camp Stoneman, California for staging to Pusan,
Korea. The 501st arrived at Pusan on 25 June 1951. The unit spent four days in the Pusan staging area awaiting sea
transportation to Inchon. The 501st arrived at Inchon on 1 July 1951. The Group Headquarters moved into the war
damaged main building of the Kyonggi Middle School, Seoul, Korea. By 15 July, the 501st had assumed
administrative and operational control of all ASA units in Korea. The 501st Communications Reconnaissance Group
represented a first of its kind and a milestone in intelligence support to U.S. tactical forces. The Korean War
presented ASA with an opportunity to test its newly formed doctrine in support of a field Army. ASA activated the
501st to direct operations of ASA support units in the Korean Theater, coordinating all ASA activities at each of the
lower echelons. By the end of hostilities in July 1953, the Group had three battalions and five companies assigned.
Besides the numerous citations awarded to its subordinate units, the Group received the Meritorious Unit
Commendation (1 July 1951 to 27 July 1953), the Republic of Korea Presidential Unit Commendation (15 July 1951
to 30 April 1953), and credit for participation in six campaigns.

On 28 January 1956, the 501st Communications Reconnaissance Group was redesignated as HHC, 501st Army
Security Group. On 1 July 1956, the 501st ASA Group was inactivated and its personnel and mission transferred to
the 508th USASA Group, a TDA organization, as part of a worldwide reorganization occurring within the Army
Security Agency to provide greater flexibility in support to tactical units.

On 1 January 1978, HHC, 501st ASA Group was redesignated HHC, 501st Military Intelligence Group and activated
at Yongsan, Korea. The Group took the place of the temporary 501st MI Group (Provisional), organized at Camp
Coiner on 1 April 1977, as part of the major reorganization within Army Intelligence which merged individual
disciplines into one organization. On 15 April 1986, the 501st was elevated to brigade status under the Army of
Excellence guidelines.
Submitted by Don Nathan, ASA Korea Member