The Main Directorate of State Security (Russian: Glavnoe Upravlenie Gosudarstvennoi Bezopasnosti, Главное управление государственной безопасности, ГУГБ, GUGB) was the name of the Soviet secret police from July 1934 to April 1943. It was run under the auspices of the Peoples Commissariat of Internal Affairs (NKVD). Its first head was first deputy of People's Commissar of Internal Affairs (then - Genrikh Yagoda), Commissar 1st rank of State Security Yakov Agranov.
Main Directorate of State Security evolved from the Joint State Political Directorate (or. OGPU). On February 3, 1941, the Special Sections (or. OO) of the GUGB-NKVD (responsible for counter-intelligence in the military) became part of the Army and Navy (RKKA and RKKF, respectively). The GUGB was removed from the NKVD and renamed Peoples Commissariat of State Security or NKGB. Following the outbreak of World War II, the NKVD and NKGB were reunited on July 20, 1941 and counter-intelligence was returned to the NKVD in January 1942. In April 1943 it was again transferred to the Narkomat of Defence and Narkomat of the Navy, becoming SMERSH (from Smert' Shpionam or "Death to Spies"); at the same time, the GUGB was again separated from the NKVD as NKGB.
By the end of 1937 GUGB was one of the most powerful and influential organs in NKVD structure. GUGB departments (or Sections) dealt with - intelligence, internal security, counter-intelligence, protection of government and secret communications.
First chief of GUGB was Yakov Agranov, Commissar 1st rank of State Security and first deputy of People's Commissar of Internal Affairs. Next chief of GUGB from April 15, 1937 to September 8, 1938 was komkor Mikhail Frinovsky, he was succeeded by Lavrenty Beria, then just promoted to Commissar 1st rank of State Security. When Beria become People's Commissar of Internal Affairs (head of NKVD), Commissar 3rd rank of State Security Vsevolod Merkulov become his first deputy and new and last head of GUGB.
Between 1934 and 1941, Main Directorate of State Security when through several organizational changes. In January 1935 in GUGB structure there were nine departments:
(head of GUGB — Commissar 1st rank of State Security Yakov Agranov)
Operational Department — Karl Pauker (headed by)
Special Department — Gleb Boki
Department of Economics - (ЭКО/EKO) — Lev Mironov
Special Department - (OO) — Mark Gay
Secret Political Department - (СПО/SPO) — Georgy Molchanov
Foreign Department - (ИНО/INO) — Artur Artuzov
Department of Transport - (ТО) — Vladimir Kichkin
Department of Information and Statistic - (УСО/USO) — Yakov Genkin
Staff Department - (OK) — Yakov Weynschtok
By the end of 1937 People's Commissar of Internal Affairs Nikolai Yezhov, in his order #00362 had change the departments number from nine to twelve.
(head of GUGB — komkor Mikhail Frinovsky)
Department 1 [Protection of Government] — Israel Dagin
Department 2 [Operative] — Ans Zalpeter
Department 3 [counter-intelligence] (КРО/KRO) — Aleksandr Minayev-Cikanovich
Department 4 [Secret Political] (СПО/SPO) — Mikhail Litvin
Department 5 [Special] (OO) — Nikolai Nikolaev- Zhuryd
Department 6 [Transport] (TO) — Mikhail Volkov
Department 7 [Foreign (Intelligence)] (ИНО/INO) — Abram Slutsky
Department 8 [Records and Statistic] (УСО/USO) — Vladimir Cesarsky
Department 9 [Special (codes)] (OO) — Isaak Shapiro
Department 10 [Prison] — Yakov Weynschtok
Department 11 [Maritime Transportation] (ВО/WO) — Victor Yrcev
Department 12 [Technical and Operational] (OOT) — Semyen Zhukovsky
After Lavrenty Beria took over Frinovsky place as a GUGB head, in September 1938, GUGB when through another organizational change:
(head of GUGB — Commissar 1st rank of State Security Lavrenty Beria)
Department 1 - [Protection of Government] — Nikolai Vlasik
Department 2 - [Secret Political] — Pyotr Fedotov
Department 3 - [counter-intelligence] — ?
Department 4 - [Special] — ?
Department 5 - [Foreign (Intelligence)] — Pavel Fitin
Department 6 - [Codes] — ?
GUGB Investigating Section — ?
генеральный комиссар ГБ — General Commissar of State Security
комиссар ГБ 1-го ранга — Commissar 1.st rank of State Security
комиссар ГБ 2-го ранга — Commissar 2.nd rank of State Security
комиссар ГБ 3-го ранга — Commissar 3.rd rank of State Security
старший майор ГБ — Senior Major of State Security
майор ГБ — Major of State Security
капитан ГБ — Captain of State Security
старший лейтенант ГБ — Senior Lieutenant of State Security
лейтенант ГБ — Lieutenant of State Security
младший лейтенант ГБ — Junior Lieutenant of State Security
сержант ГБ — Sergeant of State Security