XCOM was created in 1957 by the United States during the Cold War and as a response for the launch of the Sputnik, the first man-made satellite by the Soviet Union. Its original mission was to provide a last-resort organization to coordinate US resistance in the case of a successful communist invasion and conquest of the United States. In order to keep its existence a secret, any field operations taken to investigate possible Russian subversion activities were made under the name of the Bureau of Operations and Command, or the Bureau. The organization was originally established under the Department of Defense (DoD), and it was placed under the control of the Director of the Defense Intelligence Agency (DIA), created in 1961 to merge and coordinate the military intelligence efforts of the Army, Navy and Air Force. Its specific role of investigating any outside threat to the US in domestic soil gave it a position among the larger civilian and military intelligence agencies.
Despite being a part of the DoD, XCOM's personnel was drawn from a variety of civilian and military backgrounds, including the Armed Forces, the FBI, CIA, NSA and others. To keep the secrecy most of the personnel assigned was not aware of its existence until they were called for duty. Its first Director was Myron Faulke.