Oleg Vladimirovich Penkovsky (; 23 April 1919 – 16 May 1963), codenamed HERO, was a Soviet military intelligence (GRU) colonel during the late 1950s and early 1960s. Penkovsky informed the United States and the United Kingdom about Soviet military secrets, most importantly, the appearance and footprint of Soviet intermediate-range ballistic missile installations and the weakness of the Soviet intercontinental ballistic missile program. This information was decisive in allowing the US to recognize that the Soviets were placing missiles in Cuba before most of them were operational. It also gave US President John F. Kennedy, during the Cuban Missile Crisis that followed, valuable information about Soviet weakness that allowed him to face down Soviet leader Nikita Khrushchev and resolve the crisis without a nuclear war. Penkovsky was the highest-ranking Soviet official to provide intelligence for the West up until that time, and is one of several individuals credited with altering the course of the Cold War. He was arrested by the Soviets in October 1962, and then tried and executed the following year. Early life and military career Penkovsky never knew his father, who was killed fighting as an officer in the White Army in the Russian Civil War when he was a baby. Brought up in the North Caucasus, Penkovsky graduated from the Kiev Artillery Academy with the rank of lieutenant in 1939. After taking part in the Winter War against Finland and in World War II, he reached the rank of lieutenant-colonel. In 1944, he was assigned to the headquarters of Colonel-General Sergei Varentsov, commander of artillery on the 1st Ukrainian front, who became his patron. Penkovsky was wounded in action in 1944, at about the same time as Varentsov, who appointed him his Liaison Officer. In 1945, Penkovsky married the teenage daughter of Lieutenant-General Dmitri Gapanovich, thus acquiring another high-ranking patron. On Varentsov's recommendation, he studied at the Frunze Military Academy in 1945-48, then worked as a staff officer. Penkovsky joined the GRU as an officer, in 1953. In 1955 Penkovsky was appointed military attaché in Ankara, Turkey, but was recalled after he had reported his superior officer, and later other GRU personnel for a breach of regulations, which made him unpopular in the department. Relying once again on Varentsov's patronage, he spent nine months studying rocket artillery at Dzerzhinsky Military Academy. He was selected for the post of military attaché in India, but the KGB had uncovered