NKVD

The Soviet People's Commissariat for Internal Affairs combined ordinary policing, state security, and penal administration. Under Stalin, it organized mass arrests, executions, deportations, and the Gulag system.

Great Purge: A campaign of mass arrests, executions, and imprisonment in the Soviet Union, especially from 1936 to 1938. The NKVD carried out the campaign’s arrests and executions under Stalin.
Cheka: The Soviet political police established in 1917 to suppress counterrevolution and defend Bolshevik rule. The NKVD inherited the Cheka’s political-police role through successive reorganizations.
Joseph Stalin: The Soviet dictator who ruled the country from the late 1920s until his death in 1953. Stalin directed the political climate and policies enforced by the NKVD.
Katyn massacre: The 1940 execution by the Soviet secret police of approximately 22,000 Polish citizens, including thousands of officers. The NKVD carried out the executions on orders from the Soviet leadership.
Political repression in the Soviet Union: State action in the Soviet Union that punished or constrained people for perceived political, social, or national disloyalty. The NKVD became one of the main institutions enforcing Soviet political repression.
Gulag: The Soviet system of forced-labor camps and the administrative agency that ran it. The NKVD administered the camp system that imprisoned millions.
GPU: The Soviet political police agency established in 1922 under the Russian Soviet republic’s interior ministry. It was an institutional predecessor to the all-Union security apparatus associated with the NKVD.
Nikolai Yezhov: A Soviet official who headed the NKVD from 1936 to 1938 during the peak of the Great Purge. The mass repression of 1937–1938 became associated with his leadership.
Deportation of the Crimean Tatars: The 1944 forced deportation of the Crimean Tatar population from Crimea by Soviet authorities. NKVD forces carried out the operation, which displaced an entire people.
De-Stalinization: The Soviet political process after Stalin’s death that criticized his rule and reduced some forms of repression. The agency’s crimes became a central subject of post-Stalin condemnation and review.

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