The Mitrokhin Archive is a collection of handwritten notes about secret KGB operations spanning the period between the 1930s and 1980s made by KGB archivist Vasili Mitrokhin which he shared with British intelligence in the early 1990s. Mitrokhin, who had worked at KGB headquarters in Moscow from 1956 to 1985, first offered his material to the US's Central Intelligence Agency (CIA) in Latvia and Lithuania, but they rejected it as possible fakes. After that, he turned to the UK's MI6, which arranged his defection from Russia.

Mitrokhin secretly made his handwritten notes by copying archival documents in the period between 1972 and 1984, when he supervised the move of the archive of KGB's foreign intelligence department First Chief Directorate from the Lubyanka Building to their new headquarters at Yasenevo. When he defected to the United Kingdom in 1992, he brought the archive with him, in six full trunks. His defection was not officially announced until 1999.

The official historian of MI5, Christopher Andrew, wrote two books, The Sword and the Shield (1999) and The World Was Going Our Way: The KGB and the Battle for the Third World (2005), based on material from the Mitrokhin Archives."Just How Intelligent" The Guardian, February 18, 2003 The books provide details about many of the Soviet Union's clandestine intelligence operations around the world. They also provide specifics about Guy Burgess, a British diplomat with a short career in MI6, said to be frequently under the influence of alcohol; the archive indicates that he gave the KGB at least 389 top secret documents in the first six months of 1945, along with a further 168 in December 1949.

The utilization of the Mitrokhin Archive is not without risk because these documents only contain his handwritten notes, and no original documents or photocopies were ever made available to analyze these notes. Many scholars remain skeptical of the context and authenticity of the notes made by Mitrokhin.

Origin of the notes Vasili Nikitich Mitrokhin originally started his career with the First Chief Directorate of the KGB (Foreign Espionage) in undercover operations. After Nikita Khrushchev's Secret Speech in February 1956, which denounced the previous regime of Joseph Stalin, Mitrokhin became critical of the existing KGB system, and because of his operational failures in Israel and in Australia, he was transferred from Operations to the Archives.

Over the years, Mitrokhin became increasingly disillusioned with the Soviet system, especially after the stories about the struggles of dissidents and the 1968 invasion of Czechoslovakia, which led him to conclude that the Soviet system was incapable of reform.Christopher Andrew, "Vasili Mitrokhin" , The Guardian, 4 February 2004.

By the late 1960s, the KGB headquarters at the Lubyanka Building in central Moscow became increasingly overcrowded, and the Chairman of the KGB, Yuri Andropov, authorized the construction of a new building on the outskirts of Moscow in Yasenevo, which was to become the new headquarters of the First Chief Directorate and all foreign operations.

Mitrokhin, who was by that time the head of the Archives department, was assigned by the director of the First Directorate, Vladimir Kryuchkov, with the task of cataloging the documents and overseeing their orderly transfer to the new headquarters. The transfer of the massive archive of 300,000 files eventually took over 12 years, from 1972 to 1984."", Los Angeles Times, 3 February 2004.Andrew, Mitrokhin Archive, p. 48–52.

Unbeknown to Kryuchkov and the KGB, while cataloging the documents, Mitrokhin also secretly copied documents by hand, making immensely detailed notes, which he smuggled to his dacha in the countryside and deposited under the floorboards. Mitrokhin retired from the KGB in 1985, just after the move was completed.

During the Soviet era he made no attempt to contact any Western intelligence services, but just after the dissolution of the Soviet Union in 1991 he traveled to Latvia with copies of the material from his archive and walked into the American embassy in Riga. Central Intelligence Agency officers stationed there did not consider him to be credible, concluding that the copied documents could have been faked.

He then went to the British embassy in Vilnius (Lithuania), and a young diplomat there saw his potential. After a further meeting one month later with representatives of MI6 flown in from the UK, operations followed to retrieve the entire 25,000-page cache of files hidden in his country house, which contained details about KGB operations abroad from as far back as the 1930s.

Content of the notes Notes in the Mitrokhin Archive claim that more than half of the Soviet Union's advanced weapons were based on US designs, that the KGB tapped Henry Kissinger's phone during the time he was US Secretary of State (1973–77), and had spies in place in almost all US defense contractor facilities.

The notes also allege that some 35 senior politicians in France worked for the KGB during the Cold War. In West Germany, the KGB was said to have infiltrated the major political parties, the judiciary, and the police. Large-scale sabotage preparations were supposedly made against the US, Canada, and elsewhere in case of war, including hidden weapons caches prepared for that event; Mitrokhin's books later claimed several of these have been removed or destroyed by police relying on Mitrokhin's information.KGB in Europe, 472–476

Prominent KGB spies named in the files Melita Norwood (1912–2005), codenamed HOLA, a British civil servant who had access to state secrets while working at the British Non-Ferrous Metals Research Association between the 1930s and 1960s, and which was involved in developing Britain's nuclear weapons program.UK House of Commons, Hansard Debates, 21 Oct 1999, Columns 587–594 John Symonds (1935–2017), codenamed SKOT, a former Detective Sergeant at New Scotland Yard, who had left the UK under suspicion of corruption in the early 1970s only to be recruited by KGB in Africa.Andrew and Mitrokhin, The Mitrokhin Archive: The KGB in Europe and the West (London, 1999) pp. 559–563. He is described as having worked for the KGB between 1971 and 1980. Raymond Fletcher (1921–1991), codenamed PETER, a British journalist and subsequently Labour Party MP from 1964 to 1983; also alleged to have been recruited by the Czech secret police StB and the Central Intelligence Agency.Andrew, Mitrokhin Archive, p. 526–527. Iosif Grigulevich (1913–1988), an NKVD assassin who under a false identity served as ambassador of Costa Rica to both Italy and Yugoslavia from 1952 to 1954, and was put in charge of an aborted plan to assassinate the Yugoslav leader Josip Broz Tito Robert Lipka (1945–2013), a former clerk at the National Security Agency who passed on classified documents to the KGB in the late 1960s. Lipka had denied his involvement until the last moments before his trial was to begin 30 years later, when prosecutors revealed that the prime witness against him was a former KGB archivist.KGB in Europe, page 23–24 Salaad Gabeyre Kediye (1933–1972), codenamed OPERATOR, member of Somalia's Supreme Revolutionary Council which took over the country following the 1969 coup d'état, officially styled as "Father of the Revolution" before ending up executed in the ensuing power struggle three years later.

Latin American leaders accused of being informants or agents of the KGB Christopher Andrew states that in the Mitrokhin Archive there are several Latin American leaders or members of left wing parties accused of being KGB informants or agents. For example, leader of the Sandinistas who seized power in Nicaragua in 1979, Carlos Fonseca Amador, was described as "a trusted agent" in KGB files.The KGB in Europe, page 472–473. Quote: "Sandinista guerrillas formed the basis for a KGB sabotage and intelligence group established in 1966 on the Mexican US Border." Nikolai Leonov was Sub-Director of the Latin American Department of the KGB between 1968 and 1972. In 1998 he gave a lecture where he denied these claims, for instance Leonov claimed that said that the KGB was not called to recruit members from Communist or other left wing parties.

Daniel Ortega agreed to "unofficial meetings" with KGB officers. He gave Nikolai Leonov a secret program of the Sandinista movement (FSLN), which stated the FSLN's intent to lead class struggle in Central America, in alliance with Cuba and the Soviet bloc.The KGB and the Battle for the Third World, p. 121 Leonov claimed that he became friends with many Latin Americans including some leaders, and that he and other Soviets supported the struggles of left wing groups. But he clarifies that he did not let people know that he was a KGB agent and that his relationships with them did not involve intelligence.

Middle Eastern figures accused of being informants or agents of the KGB In September 2016, a work by two researchers (Dr. I. Ginor and G. Remez) stated that Mahmoud Abbas (also known as 'Abu Mazen'), the President of the Palestinian National Authority, worked for the Soviet intelligence agency. According to a recently released document from the Mitrokhin Archive, entitled "KGB developments – Year 1983", Abbas apparently worked under the code name "Krotov" meaning "Mole", starting early 1980s.

Alleged KGB operations revealed in the files Blackmailing Tom Driberg (code-named Lepage), British MP and a member of the executive committee of the Labour Party in the 1950s. Driberg had spied on the Communist Party of Great Britain for MI5 in the 1930s. In 1956, while visiting Moscow to interview his old friend Guy Burgess for a biography, he was blackmailed by the KGB into removing references to Burgess's alcoholism, due to their having photos of him in a homosexual encounter.Andrew, Mitrokhin Archive, p. 522–526. Attempts to increase racial hatred in the US by mailing forged hate letters to militant groupsAndrew & Mitrokhin, The Mitrokhin Archive: The KGB in Europe and the West (London, 1999) pp. 310–311. Bugging MI6 stations in the Middle EastAndrew, The KGB in Europe, p. 443. Bugging Henry Kissinger when he was serving as United States Secretary of StateAndrew, The KGB in Europe, pp. 451–453. Obtaining documents from defense contractors including Boeing, Fairchild, General Dynamics, IBM, and Lockheed Corporation, providing the Soviets with detailed information about the Trident and Peacekeeper ballistic missiles and Tomahawk cruise missilesAndrew, The KGB in Europe, p. 454. Soviet industrial espionage of Concorde supersonic passenger airliner Supporting the Sandinista movement. The leading role in this operation belonged to the General Intelligence Directorate of Communist Cuba.KGB in Europe, pages 503–505