The Great Purge or the Great Terror was a campaign of political repression in the Soviet Union which occurred from 1936 to 1938. It involved a large-scale purge of the Communist Party and government officials, repression of peasants and the Red Army leadership, and widespread police surveillance, suspicion of "saboteurs", imprisonment, and arbitrary executions. In Russian historiography, the period of the most intense purge, 1937–1938, is called Yezhovshchina (; literally, "Yezhov phenomenon", commonly translated as "times of Yezhov" or "doings of Yezhov"), after Nikolai Yezhov, the head of the Soviet secret police, NKVD.