Soviet leader Joseph Stalin consolidates the Commissariats of Home Affairs and National Security to form the NKVD and names Lavrentiy Beria its chief.

The Union of Soviet Socialist Republics (USSR), commonly known as the Soviet Union, was a transcontinental country that spanned much of Eurasia from 1922 until it dissolved in 1991. During its existence, it was the largest country by area, extending across eleven time zones and sharing borders with twelve countries, and the third-most populous country. An overall successor to the Russian Empire, it was nominally organized as a federal union of national republics, the largest and most populous of which was the Russian SFSR. In practice, its government and economy were highly centralized. As a one-party state governed by the Communist Party of the Soviet Union (CPSU), it was the flagship communist state. Its capital and largest city was Moscow.

Joseph Vissarionovich Stalin was a Soviet politician and revolutionary who led the Soviet Union from 1924 until his death in 1953. He held office as General Secretary of the Communist Party from 1922 to 1952 and as the fourth premier from 1941 until his death. Despite initially governing the country as part of a collective leadership, he ultimately consolidated power to become an absolute dictator by the 1930s. Stalin codified the party's official interpretation of Marxism as Marxism–Leninism, while the totalitarian political system he created is known as Stalinism.

The People's Commissariat for Internal Affairs, abbreviated as NKVD, was the interior ministry and secret police of the Soviet Union from 1934 to 1946. The agency was formed to succeed the Joint State Political Directorate (OGPU) secret police organization, and thus had a monopoly on intelligence and state security functions. The NKVD is known for carrying out political repression and the Great Purge under Joseph Stalin, as well as counterintelligence and other operations on the Eastern Front of World War II. The head of the NKVD was Genrikh Yagoda from 1934 to 1936, Nikolai Yezhov from 1936 to 1938, Lavrentiy Beria from 1938 to 1946, and Sergei Kruglov in 1946.