The KGB, an initialism for Komitet gosudarstvennoy bezopasnosti (Russian: Комите́т госуда́рственной безопа́сности (КГБ); translated in English as Committee for State Security), was the main security agency for the Soviet Union from 1954 until its break-up in 1991. Formed in 1954, as a direct successor of such preceding agencies as the Cheka, NKGB, and MGB, the committee was attached to the Council of Ministers. It was the chief government agency of "union-republican jurisdiction", acting as internal security, intelligence, and secret police. Similar agencies were constituted in each of the republics of the Soviet Union aside from Russia and consisted of many ministries, state committees, and state commissions.
The KGB was a military service and was governed by army laws and regulations, similar to the Soviet Army or MVD Internal Troops. While most of the KGB archives remain classified, two online documentary sources are available. Its main functions were foreign intelligence, counterintelligence, operative-investigatory activities, guarding the State Border of the USSR, guarding the leadership of the Central Committee of the Communist Party and the Soviet Government, organization and ensuring of government communications as well as combating nationalism, dissent, and anti-Soviet activities.