205th Military Intelligence Battalion. (Pacific Vigilance).
The unit first activated as the 2d Signal Service Company on 1 January 1939 at Fort Monmouth, New Jersey. The company integrated all intercept personnel of the Army's Signal Intelligence Service (SIS) into one unit. Company detachments were at several stations in the continental United States (CONUS), Panama, Hawaii, and the Philippine Islands. The company conducted the mission of obtaining the signals intelligence (SIGINT) required by the SIS.
In March 1940, as the tempo of defense activity accelerated, the company headquarters moved to Washington, D.C., bringing it nearer to SIS headquarters. Eight months later, with greater emphasis placed on the activity of the SIS, the Signal Service Company redesignated as the 2d Signal Service Battalion.
The United States' entry into World War II produced an increased number of stations. By the end of WWII, the 2d Signal Service Battalion comprised more than five thousand personnel assigned at both Arlington Hall Station (headquarters of the Signal Security Agency, SIS's successor organization) and monitoring stations worldwide. The commander of the Signal Security Agency also served as the battalion commander.
Resulting from the formation of the Army Security Agency (ASA) 20 April 1946, Headquarters Company, 2d Signal Service Battalion redesigned as Headquarters and Headquarters Company, Arlington Hall Station. Detachments of the battalion continued to operate field stations in CONUS and overseas until May 1950, when the Army disbanded the Battalion.
The Battalion reconstituted, reorganized, and redesignated as the 205th Military Intelligence Battalion effective 15 October 1992. The Battalion headquarters is at Fort Shafter, Hawaii, and subordinate elements are at Fort Richardson, Alaska; Kwajalein Atoll, Republic of the Marshall Islands; Fort Lewis, Washington; Phoenix, Arizona; and at three locations on the island of Oahu. In October 2001, the Army designated the 205th Ml Battalion as a multi-component unit. 205th MI Battalion deployed teams to East Timor in support of Operation STABILISE in 1998 and 1999. In October 2001, the 205th MI Battalion deployed soldiers to combat operations in support of Operation ENDURING FREEDOM in Uzbekistan and Afghanistan, while simultaneously supporting Operations NOBLE EAGLE and ENDURING FREEDOM - Philippines.