The Great Terror: The NKVD, the Moscow Trials, and the Gulag

The origins of the Soviet political police lie in the Cheka, founded in 1917 by Felix Dzerzhinsky, which was transformed into the GPU in 1922 and then the OGPU in 1923. The People's Commissariat for Internal Affairs (NKVD) was created in 1934, absorbing the OGPU, and its functions were expanded to include administration of the camp system, the Gulag. Genrikh Yagoda headed the NKVD during the opening phase of the Great Terror (1934-1936) before being replaced by Nikolai Yezhov in 1936, whose name became attached to the most brutal phase of repression, known as the "Yezhovshchina." Yezhov himself fell and was executed in 1940, succeeded by Lavrentiy Beria. The NKVD systematically used torture to extract confessions during interrogations and established regional quotas for arrests and executions, while mass surveillance of the population relied on networks of informants and neighbor-on-neighbor denunciation.