Cheka in the context of "Human intelligence (intelligence gathering)"

Lavrentiy Pavlovich Beria (29 March [O.S. 17 March] 1899 – 23 December 1953) was a Soviet politician and one of the longest-serving and most influential of Joseph Stalin's secret police chiefs, serving as head of the NKVD from 1938 to 1946, during the country's involvement in the Second World War.

An ethnic Georgian, Beria enlisted in the Cheka in 1920, and quickly rose through its ranks. He transferred to Communist Party work in the Caucasus in the 1930s, and in 1938 was appointed head of the NKVD by Stalin. His ascent marked the end of the Stalinist Great Purge carried out by Nikolai Yezhov, whom Beria purged. After the Soviet invasion of Poland in 1939, Beria organized the Katyn massacre of 22,000 Polish officers and intelligentsia, and after the occupation of the Baltic states and parts of Romania in 1940, he oversaw the deportations of hundreds of thousands of Poles, Balts, and Romanians to remote areas or Gulag camps. In 1940, Beria began a new purge of the Red Army. After Operation Barbarossa, the Axis invasion of the Soviet Union in June 1941, he was appointed to the State Defense Committee, overseeing security.

Palace Square (Russian: Дворцо́вая пло́щадь, romanized: Dvortsovaya Ploshchad, IPA: [dvɐrˈtsovəjə ˈploɕːɪtʲ]), connecting Nevsky Prospekt with Palace Bridge leading to Vasilievsky Island, is the central city square of St Petersburg and of the former Russian Empire. Many significant events took place there, including the Bloody Sunday massacre and parts of the October Revolution of 1917. Between 1918 and 1944, it was known as Uritsky Square (Russian: площадь Урицкого), in memory of the assassinated leader of the city's Cheka branch, Moisei Uritsky.

The earliest and most celebrated building on the square, the Baroque white-and-turquoise Winter Palace (as re-built between 1754 and 1762) of the Russian tsars, gives the square its name. Although the adjacent buildings are designed in the Neoclassical style, they perfectly match the palace in their scale, rhythm, and monumentality.The opposite, southern side of the square was designed in the shape of an arc by George von Velten in the late 18th century. These plans came to fruition half a century later, when Alexander I of Russia (reigned 1801–1825) envisaged the square as a vast monument to the 1812–1814 Russian victories over Napoleon and commissioned Carlo Rossi to design the bow-shaped Empire-style Building of the General Staff (1819–1829), which centers on a double triumphal arch crowned with a Roman quadriga.

Nikolai Stepanovich Gumilev (also Gumilyov; Russian: Николай Степанович Гумилёв, IPA: [nʲɪkɐˈlaj sʲtʲɪˈpanəvʲɪtɕ ɡʊmʲɪˈlʲɵf] ; April 15 [O.S. 3 April] 1886 – August 26, 1921) was a Russian poet, literary critic, traveler, and military officer. He was a co-founder of the Acmeist movement. He was the husband of Anna Akhmatova and the father of Lev Gumilev. Nikolai Gumilev was arrested and executed by the Cheka, the secret Soviet police force, in 1921.

The Committee for State Security (Russian: Комитет государственной безопасности, romanized: Komitet gosudarstvennoy bezopasnosti, IPA: [kəmʲɪˈtʲed ɡəsʊˈdarstvʲɪn(ː)əj bʲɪzɐˈpasnəsʲtʲɪ]), abbreviated as KGB (Russian: КГБ, IPA: [ˌkɛɡɛˈbɛ]; listen to both) was the main security agency of the Soviet Union from 1954 to 1991. It was the direct successor of preceding Soviet secret police agencies including the Cheka, OGPU, and NKVD. Attached to the Council of Ministers, it was the chief government agency of "union-republican jurisdiction", carrying out internal security, foreign intelligence, counter-intelligence and secret police functions. Similar agencies operated in each of the republics of the Soviet Union aside from the Russian SFSR, where the KGB was headquartered, with many associated ministries, state committees and state commissions.

The agency was a military service governed by army laws and regulations, in the same fashion as the Soviet Army or the MVD Internal Troops. While most of the KGB archives remain classified, two online documentary sources are available. Its main functions were foreign intelligence, counter-intelligence, operative-investigative activities, guarding the state border of the USSR, guarding the Soviet leadership, preserving the security of government communications as well as combating dissident and separatism within Soviet society.

Internal troops of the Ministry of Internal Affairs (Russian: Внутренние войска Министерства внутренних дел СССР, VV MVD) were military formations (analogous to the gendarmerie), which were intended to ensure law and public order and internal security of the Soviet Union, protect state facilities and ensure public safety. Formed in the aftermath of the October Revolution of 1917, the original internal troops, known as the Internal Security Forces of the Republic (VOHR) were created as combat detachments of the All-Russian Extraordinary Commission (Cheka). Numbering approximately 260,000 men in the 1980s, they were one of the largest formations of special troops in the Soviet Union. From September 1, 1939 to March 21, 1989, the internal troops were an integral part of the Soviet Armed Forces but were subordinate to the Ministry of Internal Affairs.

There were a succession of Soviet secret police agencies over time. The Okhrana was abolished by the Provisional government after the first revolution of 1917, and the first secret police after the October Revolution, created by Vladimir Lenin's decree on December 20, 1917, was called "Cheka" (ЧК). Officers were referred to as "chekists", a name that is still informally applied to people under the Federal Security Service of Russia, the KGB's successor in Russia after the dissolution of the Soviet Union.

For most agencies listed here, secret policing operations were only part of their function; for instance, the KGB was both a secret police and an intelligence agency.

NKVD troika or Special troika (Russian: особая тройка, romanized: osobaya troyka), in Soviet history, were special quasi-judicial proceedings composed of three officials from the security police (for much of the troikas' existence, the NKVD, hence the name) who issued sentences to people after simplified, speedy investigations and without a public trial. The three members acted as ad hoc judges. These commissions were employed as instruments of extrajudicial punishment introduced to supplement the Soviet legal system with a means for quick and secret execution or imprisonment. It began as an institution of the Cheka, then later became prominent again in the NKVD, when it was used during the Great Purge to execute many hundreds of thousands of Soviet citizens. Defendants in the Troika's proceeding were typically not entitled to legal aid or the presumption of innocence. Troika members employed common sense and socialist revolutionary principles to reach a verdict. Convictions usually did not include information about the actual incriminating evidence and basically contained only information about indictment and sentencing. The outcome of such trials was often predetermined before it even began due to targeted numbers of citizens to be executed or imprisoned in Gulag prison camps.

Troika means "a group of three" or "triad" in Russian.

The Left SR uprising, or Left SR revolt, was a rebellion against the Bolsheviks by the Left Socialist Revolutionary Party in Moscow, Soviet Russia, on 6–7 July 1918. It was one of a number of left-wing uprisings against the Bolsheviks that took place during the Russian Civil War.

The Left SRs had entered the Bolshevik government of Soviet Russia after the October Revolution of 1917, but resigned from the Council of People's Commissars in March 1918 in protest of the Treaty of Brest-Litovsk. Left SRs continued to work in other organizations (notably the Cheka) while denouncing the treaty and the policy of requisitioning grain from the peasants.