The company served in the Southwest Pacific Theater during World War II, then moved to Japan to join the occupation forces.

The unit's mission is to collect, process, analyze, and report signals intelligence on adversary operations, capabilities, and intentions.

[2] The first predecessor of the squadron was activated in February 1942 as the 138th Signal Intelligence Company at Fort George Wright, Washington.

[5] When the North Koreans crossed the 38th parallel and invaded in June 1950, the squadron's commander ordered its vehicles to be laagered on the Johnson Air Base football field in case of a parachute attack on Japan.

However Fifth Air Force had established its own ad hoc signals intelligence party near Seoul, which commandeered the 1st Squadron's equipment.

[6] In March 1951, squadron operators in Japan began picking up voice communications in Russian between ground controllers and Mikoyan-Gurevich MiG-15 fighters.

By April, the squadron had established a mobile van in central Korea, which passed information on MiGs to the Fifth Air Force tactical air control center, which passed it on to American North American F-86 Sabres, disguising the information to make it appear that it was coming from radar ground stations, even though the radio intercept van could provide warning of Soviet aircraft movements well beyond the range of American radars.

[7] In January 1951, the squadron moved to Misawa Air Base, Japan, where one of the first Elephant Cage high frequency direction finding antenna assemblies was located.