When did the campaign of political  repression that Mikhail Demichev was arrested during occur?
Mikhail Demichev Mikhail Demichev (1885 – November 19, 1937) was a Soviet Komdiv (division commander). He fought in the Imperial Russian Army in World War I before going over to the Bolsheviks in the subsequent civil war. He was a recipient of the Order of the Red Banner. During the Great Purge, he was arrested on August 9, 1937 and later executed. After the death of Joseph Stalin, he was rehabilitated in 1956.
Joint State Political Directorate The Joint State Political Directorate (also translated as the All-Union State Political Administration and Unified State Political Directorate) was the secret police of the Soviet Union from 1923 to 1934. Its official name was "Joint State Political Directorate under the Council of People's Commissars of the USSR" (Russian: Объединённое государственное политическое управление при СНК СССР)", Obyedinyonnoye gosudarstvennoye politicheskoye upravleniye pri SNK SSSR", or ОГПУ (OGPU).